The Federation of the World

On June 25, 1945, a hulking C-54 military transport plane descended through foggy skies to touch down at Hamilton Airforce Base north of San Francisco. Waiting on the tarmac were US Secretary of State Edward Stettinius, California Governor Earl Warren, and the heads of forty-nine foreign delegations from around the world.Footnote ¹ As a military guard saluted and a brass band played, US President Harry Truman emerged from the plane wearing a grey double-breasted suit, a blue bowtie, and an exultant smile. Although war with Japan raged on in the Pacific, Truman’s spirits were high, and for good reason. He had come to witness the birth of a new world order – one intended to end war for generations to come.

Nine weeks earlier, diplomats and heads of state had gathered in San Francisco at the invitation of Truman’s predecessor, Franklin Roosevelt, with an ambitious goal: to lay the foundation for a peaceful postwar order.Footnote ² Almost overnight, the City by the Bay cast aside years of wartime austerity, exchanging food rationing and blackouts for decadent parties awash with light and music, where foreign diplomats rubbed shoulders with Hollywood stars. Reporters from around the world descended in record numbers, including the young Navy hero and future US president, John Kennedy. While the press flocked to the conference’s plenary sessions at the stately San Francisco Opera House, the most consequential proceedings took place across town in Secretary Stettinius’s penthouse suite at the Fairmont Hotel on Nob Hill.Footnote ³ Representatives of the “Big Five” – China, France, the Soviet Union, the United Kingdom, and the United States – met daily to hammer out the final details of a plan, announced two years earlier in Moscow, for “a general international organization, based on the principle of sovereign equality of all peace-loving states, and open to membership by all such states, large and small, for the maintenance of international peace and security.”Footnote ⁴

Truman championed the conference’s agenda. From his youth, Truman had carried in his wallet a folded copy of several stanzas from a favorite poem by Lord Tennyson that envisioned international cooperation fostering a more peaceful world:

In the months preceding the San Francisco Conference, Truman had urged his compatriots to embrace this vision of a “Federation of the world” as the formula for enduring peace and security.Footnote ⁶ “The policy we hope and believe will emerge from the San Francisco Conference and others to follow will embody cooperation among nations to keep down aggressors,” he explained to an audience in his home state of Missouri. “The only rational alternative to existing anarchy lies in some reasonable form of international organization among so-called sovereign states.”Footnote ⁷

Thus, it was with great excitement that Truman arrived in San Francisco to join the final sessions of the conference. After greeting the assembled dignitaries, Truman led a motorcade of nearly a hundred limousines flanked by motorcycle police across the Golden Gate Bridge, where 500,000 residents – the largest crowd in the city’s history – gathered to cheer on the procession.Footnote ⁸ Later that evening, thousands packed into the Opera House to see the fifty national delegations rise from their seats to adopt the Charter of the United Nations unanimously.Footnote ⁹

The following day, as delegates reassembled for the Charter’s signing ceremony, the conference’s secretary-general, Alger Hiss, praised the participants for changing the course of history. He reminded them that the Charter affirms the proposition that “we all have to recognize – no matter how great our strength – that we must deny ourselves the license to do always as we please … This is the price which each nation will have to pay for world peace.”Footnote ¹⁰ Truman then rose to underscore the importance of international cooperation to ensure the venture’s ultimate success. He declared: “We have tested the principle of cooperation in this war, and we have found it works.”Footnote ¹¹

Eighty years later, the Charter’s ambitious framework for international cooperation remains formally intact, but its promise only partly fulfilled.Footnote ¹² Mandatory cooperation under the Charter entails essentially the same legal requirements as in other domains where it arises: states must consult, evaluate risks, share relevant information, and pursue peaceful dispute resolution with one another. When threats to peace and security emerge, states must cooperate through the United Nations to keep “a fretful realm in awe.” In addition, states must work together to address the root causes of human immiseration which undermine international peace and security, including atrocity crimes and global poverty. If the United Nations has struggled to deliver international peace and security and universal respect for human rights, the fault lies in large measure with states that have defaulted on their obligations of mandatory cooperation.

Uniting for International Peace and Security

Just as international cooperation at the San Francisco Conference gave birth to the United Nations, the Charter relies on international cooperation “to save succeeding generations from the scourge of war” and to “reaffirm faith in fundamental human rights, in the dignity and worth of the human person,” and “in the equal rights of men and women and of nations large and small.”Footnote ¹³ In the Charter’s preamble, UN member states express their determination “to practice tolerance and to live together in peace with one another as good neighbours.”Footnote ¹⁴ Article 2(4) obligates them to “refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any state, or in any other manner inconsistent with the Purposes of the United Nations.”Footnote ¹⁵ When international disputes arise, states must strive “in good faith” to resolve their differences “by peaceful means in such a manner that international peace and security, and justice, are not endangered.”Footnote ¹⁶ These requirements of mandatory cooperation safeguard the sovereign equality of individual UN member statesFootnote ¹⁷ while also attending to the international community’s collective interest in preserving a peaceful world order.Footnote ¹⁸

Recognizing that states might be tempted to violate these obligations, the Charter establishes the United Nations as a secondary guarantor of international peace and security. The preamble conveys the international community’s aspiration “to unite our strength” to preserve the peace, thereby ensuring “that armed force shall not be used, save in the common interest.”Footnote ¹⁹ To this end, Article 1 specifies four general purposes of the United Nations:

The Charter tasks the Security Council with coordinating the United Nations’ efforts to preserve international peace and security.Footnote ²¹ Some of the Security Council’s powers relate to encouraging states to settle their disputes through peaceful cooperation. For example, the Security Council may call upon states to embrace negotiation, mediation, conciliation, arbitration, adjudication, or other peaceful means of dispute resolution.Footnote ²² If these efforts fail, states must refer their disputes to the Security Council so that it can “recommend such terms of settlement as it considers appropriate.”Footnote ²³ The Security Council may also take action on its own initiative to investigate “any situation which might lead to international friction or give rise to a dispute, in order to determine whether the continuance of the dispute or situation is likely to endanger the maintenance of international peace and security.”Footnote ²⁴

Chapter VII of the Charter empowers the Security Council to compel recalcitrant states to take whatever steps it deems necessary to maintain international peace and security. When the Security Council identifies a threat to the peace, a breach of the peace, or an act of aggression, it may not only “make recommendations” to states but also “decide what measures shall be taken … to maintain or restore international peace and security.”Footnote ²⁵ This may include provisional measures “to prevent an aggravation of the situation” or coercive “measures not involving the use of force” (e.g., economic sanctions, travel bans).Footnote ²⁶ The Security Council may even authorize using military force to preserve or restore international peace and security (e.g., naval blockades, air strikes, peacekeeping, and peacebuilding missions).Footnote ²⁷

Significantly, the Charter obligates all states to cooperate with the Security Council’s efforts to prevent and suppress threats to international peace and security – not just those directly responsible for the threats. Under Article 25, “Members of the United Nations agree to accept and carry out the decisions of the Security Council.”Footnote ²⁸ States also pledge in Article 2(5) “to give the United Nations every assistance in any action it takes” to maintain international peace and security, as well as to “refrain from giving assistance to any state against which the United Nations is taking preventive or enforcement action.”Footnote ²⁹ States that violate these obligations expose themselves to international censure, as well as sanctions and other coercive measures, as directed by the Security Council.Footnote ³⁰ Thus, when the Security Council finds a threat to the peace or a breach of the peace, all states are obligated under the Charter to follow its lead.Footnote ³¹

In its landmark 1970 Declaration on Principles of International Law Concerning Friendly Relations and Co-operation Among States in Accordance with the Charter of the United Nations (Friendly Relations Declaration), the UN General Assembly affirmed that states bear due diligence obligations to promote the Charter’s general purposes. In particular, the Friendly Relations Declaration states that “[a]ll states shall comply in good faith with their obligations under the generally recognized principles and rules of international law with respect to the maintenance of international peace and security, and shall endeavor to make the United Nations security system based on the Charter more effective.”Footnote ³² Hence, states must settle their disputes peacefully “on the basis of the sovereign equality of States and in accordance with the principle of free choice of means” and cooperate with other states and the United Nations to maintain international peace and security.Footnote ³³

Some international lawyers might object that the Charter’s cooperative framework for collective security is undermined by Article 51, which permits states to defend themselves from attack without awaiting Security Council authorization.Footnote ³⁴ In principle, however, a state’s “inherent right” of self-defense under Article 51 is compatible with the Charter’s commitment to mandatory cooperation through the United Nations.Footnote ³⁵ Article 51 authorizes self-defense only when an actual or imminent attack has already ruptured international peace and security and only until the Security Council intercedes.Footnote ³⁶ The Charter stipulates that an act of “self-defense shall be immediately reported to the Security Council and shall not in any way affect the authority and responsibility of the Security Council” to prescribe a multilateral response.Footnote ³⁷ Self-defense under Article 51 is also subject to customary requirements of necessity and proportionality, which require states to consider the impact of their defensive measures on foreign interests.Footnote ³⁸ Therefore, even when states act in self-defense, international law channels their response through multilateral norms and processes to prevent states from using force “save in the common interest” to liberate humanity “from the scourge of war.”Footnote ³⁹

An Early Victory

Less than two months after the San Francisco Conference, the United Nations received an early stress test in Indonesia. On the morning of August 7, 1945 – two days after the surrender of Japan’s occupying forces – Indonesian nationalist republicans assembled at the home of their leader, Sukarno, in Djakarta. Sukarno read from a slip of paper: “We the Indonesian people proclaim the independence of Indonesia.” He then stood at attention while a simple red-and-white flag rose into the sky, asserting the birth of a new state – one that demanded independence not only from Japan but also from its British “liberators” and the Dutch colonialists who had governed before the war.Footnote ⁴⁰ Before long, hostilities broke out between Indonesia’s independence movement and British occupying forces. Meanwhile, the Netherlands readied plans for its own military action to retake the Indonesian archipelago.Footnote ⁴¹

Such were the circumstances in Indonesia in January 1946, when the Security Council gathered for its first session at Church House, its temporary London headquarters near Westminster Abbey. On the agenda were several pressing topics, including a proposal from Ukraine to address the escalating violence in Indonesia. Ukraine accused Japan and the United Kingdom of threatening international peace and security by occupying Indonesia illegally and conducting military operations against Indonesian civilians. The British vigorously disputed these charges, insisting that they had no intention of remaining in Indonesia and were simply trying to restore order and protect their troops from attack pending an orderly withdrawal.Footnote ⁴² Although the United Kingdom formally recognized Dutch sovereignty over Indonesia, British leaders attempted to prevent the Dutch from landing in Java and Sumatra and sought to broker a peaceful settlement between the Netherlands and Indonesian republicans.Footnote ⁴³

Ukraine’s proposal for Security Council action on Indonesia came up short of the necessary votes. However, when negotiations between the Netherlands and the Indonesian independence movement collapsed, prompting the Dutch to attempt to reestablish colonial rule by force, the Security Council revisited the matter at the request of Australia and India.Footnote ⁴⁴ The Netherlands, which then occupied a non-permanent seat on the Security Council, argued that the United Nations lacked jurisdiction to intercede because Indonesia fell within the Netherlands’ sovereign jurisdiction, making the issue a matter of exclusively domestic concern.Footnote ⁴⁵ No other Security Council member accepted this argument. Instead, on August 1, 1947, the Security Council, for the first time in its history, adopted a resolution demanding a ceasefire and calling on the parties to settle their dispute by arbitration or other peaceful means.Footnote ⁴⁶ Within days, both sides complied with the Security Council’s directive.Footnote ⁴⁷ The New York Times reported “that the United Nations had probably won its first major victory and through this victory had given the new international organization a sorely needed boost in prestige.”Footnote ⁴⁸

The next several years in Indonesia witnessed recurring cycles of negotiation, violent clashes, and UN-brokered ceasefires. The Security Council demanded that the Netherlands and Indonesian republicans cooperate with an international mission established to investigate and mediate their dispute.Footnote ⁴⁹ After the Security Council set a timetable for Indonesian independence, the Netherlands eventually agreed to withdraw its military and formally transferred sovereignty to the Indonesian state on December 27, 1949.Footnote ⁵⁰ International cooperation through the Security Council thus ended violent conflict and Dutch colonial rule, paving the way for international recognition of the sovereign Republic of Indonesia. On September 28, 1950, Indonesia became the sixtieth member of the United Nations.Footnote ⁵¹

Collective Enforcement in Fits and Starts

The Security Council’s engagement with Indonesia offered proof of concept that mandatory cooperation through the United Nations could perform a constructive role in maintaining international peace and security. The Security Council used various tools to achieve a peaceful settlement in Indonesia, including consultation, investigation, mediation, and legally binding resolutions. Encouraged by the preliminary results, the Security Council over the next several years applied these and other tools (albeit with mixed results) in various conflict zones, including the Balkans, Greece, Kashmir, and Palestine.Footnote ⁵² Among the Security Council’s early efforts at crisis management, however, it was the Korean War that most seriously tested the Charter’s framework for mandatory cooperation.

When North Korea invaded South Korea on June 25, 1950, it committed the kind of unprovoked aggression that the Charter’s drafters had in mind when they outlawed the “use of force against the territorial integrity or political independence of any state.”Footnote ⁵³ The United States requested a meeting of the Security Council and circulated a draft resolution condemning the North Korean attack. The draft demanded North Korea’s immediate and total withdrawal and called upon “all Member States to render every assistance to the United Nations in the execution of this resolution and refrain from giving assistance to the North Korean authorities.”Footnote ⁵⁴ With the People’s Republic of China not represented at the Security Council (the seat designated for China was occupied by Taipei rather than Beijing) and the Soviet Union boycotting the United Nations, the United States’ draft sailed through the Security Council to become Resolution 82.Footnote ⁵⁵ Two days later, the Security Council recommended that UN member states “furnish such assistance to the Republic of Korea as may be necessary to repel the armed attack and to restore international peace and security in the area.”Footnote ⁵⁶ For the first time in its history, the Security Council had invited states to defend a state under attack.Footnote ⁵⁷ By mid-September 1950, fourteen states had contributed ground forces to South Korea’s defense, and dozens of others had furnished material assistance.Footnote ⁵⁸

Whatever hopes the United States and its allies may have placed in the Security Council to rally international cooperation against North Korean aggression, the limits of this strategy soon became apparent. In Resolution 82 and subsequent resolutions, the Security Council stopped short of mandating bystander state cooperation under Articles 40–42 of the Charter. Once the Soviet Union resumed participating in Security Council meetings, its veto power prevented the Security Council from further addressing the Korean War. As a result, the Security Council lost meaningful supervisory control over South Korea’s collective defense.Footnote ⁵⁹ Just five years removed from the halcyon days of the San Francisco Conference, several of the “Big Five” states that had brought the UN Charter into the world already found themselves on opposite sides of a bloody conflict.

The incipient Cold War tensions that fueled the Korean War significantly impacted the Security Council as an institution. For the next four decades, the Security Council rarely mustered the votes necessary to respond to threats to international peace and security. However, the Security Council often invited states to cooperate in peaceful dispute resolution, and it occasionally deployed peacekeeping missions to conflict zones.Footnote ⁶⁰ For example, in the United Nations’ first formal peacekeeping mission (UNEF I), international peacekeepers helped to defuse the 1956 Suez Crisis by supervising the orderly withdrawal of British, French, and Israeli armed forces from Egypt.Footnote ⁶¹ A decade later, the Security Council, for the first time, imposed mandatory economic sanctions against Southern Rhodesia (present-day Zimbabwe) to compel its white-dominated apartheid government to relinquish power.Footnote ⁶² These measures demonstrated the United Nations’ potential to galvanize international cooperation for international peace and security. More often than not, however, hardened rivalries among the Security Council’s P5 hamstrung the Security Council’s ability to prevent and suppress violent conflicts worldwide. Perhaps the Security Council’s primary contribution during this era, therefore, was simply to foster dialogue, reducing the risks of misunderstanding and direct military confrontation among the world’s great powers.Footnote ⁶³

As relations among the P5 began to thaw in the late 1980s, the Security Council became more assertive in countering threats to international peace and security. When Iraq invaded Kuwait in August 1990, the Security Council held an emergency meeting and quickly passed a resolution ordering Iraq to withdraw “immediately and unconditionally.”Footnote ⁶⁴ Hard on the heels of this resolution came additional directives, urged by the United States and the United Kingdom but supported by most other states, declaring the annexation of Kuwait null and void, imposing a comprehensive sanctions regime on Iraq, and establishing a special committee to monitor compliance.Footnote ⁶⁵ By the end of November, the Security Council invoked its authority under Chapter VII of the Charter and gave Iraq until January 15, 1991, to withdraw from Kuwait. The Security Council authorized other states to use “all necessary means” – including military action – to expel Iraq once the deadline for voluntary withdrawal passed.Footnote ⁶⁶ Backed by the Security Council, a coalition of thirty-six nations proceeded to drive the Iraqi army from Kuwait through several weeks of aerial bombardment and an intense but brief 100-hour ground campaign.Footnote ⁶⁷

In 2003, the United States led a second military campaign against Iraq with significantly less international support. In the lead up to the war, the United States sent Secretary of State Colin Powell to the United Nations to make the case for military action to topple the regime of Saddam Hussein. Powell testified based on faulty evidence that “the facts and Iraq’s behavior show that Saddam Hussein and his regime are concealing their efforts to produce more weapons of mass destruction.”Footnote ⁶⁸ With a majority of the Security Council including Russia and France opposed to military action in Iraq, the United States, United Kingdom, and Spain abandoned last-ditch efforts to win UN backing, with British Ambassador Jeremy Greenstock advising that the trio “reserve their right to take their own steps to secure the disarmament of Iraq.”Footnote ⁶⁹ While the Security Council did not authorize military action against Iraq in 2003, it also proved incapable of thwarting two Great Powers from using military force to impose regime change and a lengthy occupation on Iraq. The Iraq War is a potent reminder that the effectiveness of the UN system depends on the willingness of its more powerful members to abide by its Charter and international law generally.

Cooperating to Respect, Protect, and Fulfill Human Rights

Since the 1990s, the Security Council has devoted increasing attention to preventing and suppressing human rights crises around the world. The groundwork for this effort was laid during the San Francisco Conference. Recall that a core purpose of the United Nations, as set forth in Article 1 of the Charter, is to “achieve international co-operation in solving international problems of an economic, social, cultural, or humanitarian character, and in promoting and encouraging respect for human rights and for fundamental freedoms for all without distinction as to race, sex, language, or religion.”Footnote ⁷⁰ The drafters of the Charter believed that these “conditions of stability and well-being” within states were an essential prerequisite for “peaceful and friendly relations among nations based on the principle of equal rights and self-determination of peoples.”Footnote ⁷¹ States are primarily responsible under the Charter for ensuring that their people enjoy the full protection of international human rights within their respective jurisdictions. Under Articles 55 and 56, however, they also “pledge themselves to take joint … action in co-operation with the [United Nations]”Footnote ⁷² to guarantee “universal respect for, and observance of, human rights and fundamental freedoms for all.”Footnote ⁷³ Thus, just as states must cooperate with the Security Council’s efforts to maintain international peace and security, the Charter also requires states to cooperate with one another and the United Nations to protect and fulfill human rights worldwide.

Early in the United Nations’ history, states worked through the General Assembly and the UN Economic and Social Council (ECOSOC) to specify international human rights norms in landmark agreements, such as the Universal Declaration of Human Rights,Footnote ⁷⁴ the International Covenant on Civil and Political Rights,Footnote ⁷⁵ and the International Covenant on Economic, Social and Cultural Rights (ICESCR).Footnote ⁷⁶ Over the past several decades, however, the United Nations’ focus generally has shifted from norm-specification and legal codification to securing compliance with established human rights obligations. Protecting human rights has become a core purpose of UN peacekeeping.Footnote ⁷⁷ The Security Council has exercised its Chapter VII authority with increasing regularity to mandate collective enforcement measures (e.g., economic sanctions, travel restrictions, military action) and to prevent and suppress serious breaches of international human rights norms (e.g., crimes against humanity and war crimes).Footnote ⁷⁸ Along the way, the international community has accepted that all states must cooperate when the Security Council decides that international cooperation is necessary to advance universal respect for international human rights.Footnote ⁷⁹

One of the ways states have pledged to promote respect for international human rights is by cooperating with one another and with international tribunals to facilitate the prosecution of those who commit international crimes. During the 1990s, the UN Security Council established ad hoc criminal tribunals to investigate and prosecute mass atrocities in Rwanda and the former Yugoslavia.Footnote ⁸⁰ In both settings, the Security Council issued binding regulations requiring states to cooperate with the tribunals, including by complying with requests for assistance with pretrial investigation and prosecution.Footnote ⁸¹ States later incorporated duties of cooperation into the Rome Statute of the International Criminal Court (ICC).Footnote ⁸² The Rome Statute requires states-parties to “cooperate fully with the Court in its investigation and prosecution of crimes within the jurisdiction of the Court,”Footnote ⁸³ including by gathering evidence, securing witnesses for trial, and arresting and surrendering suspects upon the Court’s request.Footnote ⁸⁴ Mandatory cooperation also features prominently in the Convention Against Torture and Other Cruel, Inhuman, or Degrading Treatment or Punishment.Footnote ⁸⁵ States-parties must not only prevent, criminalize, and prosecute domestic acts of tortureFootnote ⁸⁶ but also grant reasonable extradition requests and “afford one another the greatest measure of assistance in connection with criminal proceedings brought” to enforce the Convention, including by providing “all evidence at their disposal necessary for the proceedings.”Footnote ⁸⁷ Similar duties of international cooperation appear in the International Convention for the Protection of All Persons from Enforced DisappearanceFootnote ⁸⁸ and the Convention on the Prevention and Punishment of the Crime of Genocide (Genocide Convention).Footnote ⁸⁹

The Bosnian Genocide Case

On July 11, 1995, at the height of the violence unleashed by Yugoslavia’s dissolution, Bosnian Serbs under the command of General Radko Mladić captured the weakly fortified town of Srebrenica on the eastern fringe of present-day Bosnia and Herzegovina. Stationed at Srebrenica was a small contingent of Dutch peacekeepers operating under UN mandate but without authorization to use force for the town’s defense. Two years earlier, the Security Council had adopted a resolution designating “Srebrenica and its surroundings as a safe area which should be free from any armed attack or any other hostile act.”Footnote ⁹⁰ As Mladić entered town, however, he looked directly into a journalist’s video camera and declared, “We give this town to the Serb nation as a gift. The time has come to take revenge on the Muslims.”Footnote ⁹¹ Over the next five days, Mladić’s troops systematically rounded up and executed over 7,000 unarmed Muslim men of all ages.Footnote ⁹²

Even before the massacre at Srebrenica, Bosnia and Herzegovina had instituted proceedings in the ICJ, claiming that Serbia was legally responsible for atrocities committed on Bosnian soil by Bosnian Serb separatists.Footnote ⁹³ These proceedings gained even greater urgency after the much-publicized Srebrenica massacre. Bosnia and Herzegovina argued that Serbia violated the Genocide Convention by failing to prevent acts of genocide by Bosnian Serbs and declining to arrest and surrender General Mladić for prosecution in the International Criminal Tribunal for the Former Yugoslavia (ICTY).Footnote ⁹⁴ These legal claims raised important questions about the scope of mandatory cooperation as applied to mass atrocities. Did Serbia indeed have an affirmative obligation to prevent the Srebrenica genocide and punish those responsible? Should it make a difference that the genocidal acts were committed by foreign nationals (Bosnian Serbs) outside Serbian territory?

In its landmark judgment of February 26, 2007, the ICJ agreed that Serbia violated the Genocide Convention by failing to cooperate fully with international efforts to prevent the massacre at Srebrenica and punish Mladić.Footnote ⁹⁵ Although the Court found insufficient evidence to attribute the Srebrenica genocide to Serbia,Footnote ⁹⁶ it underscored Serbia’s affirmative obligation to prevent and punish genocide:

The ICJ acknowledged that a state’s legal responsibility to prevent others from committing genocide varies depending upon its “capacity to influence effectively the action of persons likely to commit or already committing, genocide,” as well as “its particular legal position vis-à-vis the situations and persons facing the danger, or the reality, of genocide.” However, the fact that a state might not be able to prevent genocide through its efforts alone would not suffice to excuse a failure to act. Instead, the proper inquiry was whether “the combined efforts of several States, each complying with its obligation to prevent, might have achieved the result – averting the commission of genocide – which the efforts of only one State were insufficient to produce.”Footnote ⁹⁸ Put simply, when a state cannot prevent genocide unilaterally, it must pursue international cooperation.Footnote ⁹⁹ In the case of Srebrenica, the ICJ concluded that Serbia violated its obligations under the Genocide Convention by failing to devote “the best efforts within [its] power to try and prevent the tragic events then taking shape.”Footnote ¹⁰⁰

This was not Serbia’s only violation of international law. The ICJ also concluded that Serbia “failed in its duty to co-operate with the ICTY.”Footnote ¹⁰¹ According to the Court, states-parties to the Genocide Convention must “arrest persons accused of genocide who are in their territory – even if the crime of which they are accused was committed outside it – and, failing prosecution of them in the parties’ own courts,” they must “hand them over for trial by the competent international tribunal.”Footnote ¹⁰² The Court found “plentiful, and mutually corroborative, information suggesting that General Mladić, indicted by the ICTY for genocide,” had been living freely in Serbian territory with the knowledge of Serbia’s intelligence service but without Serbia taking reasonable steps to make an arrest.Footnote ¹⁰³ This failure to cooperate fully with the ICTY violated Serbia’s duties “as a member of the United Nations” and “under Article VI of the Genocide Convention.”Footnote ¹⁰⁴

Cooperating to Prevent and Punish Other Atrocity Crimes

The Bosnian Genocide Case confirms that states bear due diligence obligations to prevent and suppress genocide and that they must cooperate with one another and with international organizations to make those efforts effective. The judgment does not directly address whether states must unite to prevent and suppress other international crimes. Still, there are strong signals elsewhere in the ICJ’s jurisprudence that all such crimes trigger mandatory cooperation. For example, in the Reservations to the Genocide Convention Case (Reservations Case), the Court explained that mandatory cooperation is a “consequence” of the Genocide Convention’s “conception” of genocide as an international crime which “shocks the conscience of mankind and results in great losses to humanity, and which is contrary to moral law and to the spirit and aims of the United Nations.”Footnote ¹⁰⁵ Based on this logic, it would seem to follow that states must cooperate to prevent, suppress, and punish other mass atrocities, as well. Genocide is not the only universally recognized international crime that shocks the conscience, generates great losses to humanity, and violates the spirit and aims of the United Nations; the crime of aggression, crimes against humanity, and at least some war crimes clearly satisfy these criteria.Footnote ¹⁰⁶ The ICJ’s reasoning in the Reservations Case suggests, therefore, that those other international crimes also trigger an obligation to cooperate in good faith “to liberate mankind from such an odious scourge.”Footnote ¹⁰⁷

Consistent with the Reservations Case, customary international law may be in the process of establishing positive duties of cooperation for grave breaches of international human rights and international criminal law. In its influential 2001 Articles on State Responsibility for Internationally Wrongful Acts (the Articles), the UN International Law Commission (ILC) concluded that under international law, states must “cooperate to bring to an end through lawful means any serious breach” “of an obligation arising under a peremptory norm of general international law.”Footnote ¹⁰⁸ The ILC’s commentary accompanying the Articles acknowledges that reasonable minds might question whether “[customary] international law at present prescribes a positive duty of cooperation,” and it concedes that the Articles’ articulation of this duty “may reflect the progressive development of international law.”Footnote ¹⁰⁹ Nonetheless, the ILC’s commentary observes that “in fact such cooperation, especially in the framework of international organizations, is carried out already in response to the gravest breaches of international law.”Footnote ¹¹⁰

Since the ILC finalized the Articles, the idea that states must cooperate to prevent mass atrocities has received some additional support from the UN General Assembly. In the 2005 World Summit Outcome, 191 states unanimously endorsed the “Responsibility to Protect” (R2P) doctrine, affirming that states are responsible for protecting their people from genocide, war crimes, ethnic cleansing, and crimes against humanity, and that “[t]he international community, through the United Nations, also has the responsibility to use appropriate … means” – including “collective action … through the Security Council” – to protect vulnerable populations from these threats.Footnote ¹¹¹ A year after the 2005 World Summit Outcome, the General Assembly clarified further that “[i]n cases of gross violations of international human rights law and serious violations of international humanitarian law constituting crimes under international law, … States should, in accordance with international law, cooperate with one another and assist international judicial organs competent in the investigation and prosecution of these violations.”Footnote ¹¹² At a minimum, these General Assembly resolutions express a shared political commitment to cooperate to prevent and punish international crimes.

Whether states accept the idea that they have a legal obligation to cooperate to prevent and suppress atrocity crimes is less clear. In practice, bystander states rarely treat international cooperation as a legal requirement absent a binding Security Council resolution. The international community’s flagrant failures to prevent genocide and crimes against humanity in Cambodia, Rwanda, Bosnia, Darfur, Syria, Myanmar, and elsewhere are well documented.Footnote ¹¹³ As these crises have unfolded, many states have turned a blind eye to imminent catastrophe. Security Council members have opposed or slow-rolled proposals to protect vulnerable populations. Reflecting on these tragedies in a 2016 Report titled Mobilizing Collective Action: The Next Decade of the Responsibility to Protect, UN Secretary-General Ban Ki-Moon lamented that “although Member States have repeatedly emphasized their support for the prevention of atrocity crimes, this has not been sufficiently translated into concrete support for preventive strategies – even when there have been credible assessments of imminent threats to populations.”Footnote ¹¹⁴ Experience thus reveals a wide gap between international institutions’ strong affirmations of mandatory cooperation to prevent and punish atrocity crimes, on the one hand, and tepid state practice, on the other hand.

The genocide in Sudan’s Darfur region (2003–2005) illustrates this challenge. In October 2003 – at least three months before international news media began reporting ethnic cleansing by Janjaweed militia in Darfur, and a full eleven months before Western governments officially labeled the attacks “genocide” – the US State Department was aware that escalating ethnic violence in the region could soon cause death rates to spike into the hundreds of thousands. The European Commission also tracked developments in Darfur closely and anticipated imminent calamity. Nonetheless, early warnings about the approaching genocide were “swept under the carpet” based on “a conscious decision to address Darfur silently using quiet diplomacy and not bring it to the UN Security Council.”Footnote ¹¹⁵ Had the European Commission and the United States recognized that the looming crisis triggered mandatory cooperation – including a firm due diligence obligation to notify the entire international community of the approaching calamity and seek timely action from the Security Council – this might have helped to avert or contain the atrocities that followed. Attending to the requirements of mandatory cooperation might have helped to persuade Security Council members, as “trustees of the international community,” to act more decisively to condemn, prevent, and suppress mass murder in Darfur.Footnote ¹¹⁶

Or perhaps not. Even when requirements of mandatory cooperation are well recognized and uncontroversial, states are not always eager to comply with their obligations. For example, in March 2009, the ICC issued a warrant for the arrest of Sudanese President Omar al-Bashir for his role in the Darfur genocide.Footnote ¹¹⁷ Under the Rome Statute and the Genocide Convention, all states-parties are obligated to cooperate in bringing al-Bashir to justice. Nonetheless, in the years that followed, over twenty countries welcomed visits from al-Bashir without executing his arrest, including China, Egypt, Ethiopia, Indonesia, Iran, Kenya, Russia, Saudi Arabia, the United Arab Emirates, and South Africa.Footnote ¹¹⁸ Although Sudan has pledged to deliver al-Bashir to the ICC for trial,Footnote ¹¹⁹ thus far it has not followed through on this commitment. The ICC has referred instances of state noncooperation to the Security Council, but its requests have been brushed aside. These failures of cooperation suggest that some states lack the political will to prioritize punishing atrocity crimes.

Cooperating for Economic, Social, and Cultural Rights

Economic, social, and cultural rights also trigger mandatory cooperation under international human rights law. The ICESCR enshrines a wide variety of rights, such as the right to work and the right to “an adequate standard of living … , including adequate food, clothing and housing, and to the continuous improvement of living conditions.”Footnote ¹²⁰ Article 2(1) declares that these rights are subject to mandatory cooperation: “Each State Party to the present Covenant undertakes to take steps, individually and through international assistance and co-operation, especially economic and technical, to the maximum of its available resources, with a view to achieving progressively the full realization of the rights recognized in the present Covenant by all appropriate means, including particularly the adoption of legislative measures.”Footnote ¹²¹ In addressing the right to an adequate standard of living, the Convention provides that international assistance and cooperation could improve methods of food production, conservation, and dissemination; disseminate agricultural techniques and best practices; and “ensure an equitable distribution of world supplies in relation to need.”Footnote ¹²² States-parties “agree that international action for the achievement of the rights recognized in the … Covenant includes such methods as the conclusion of conventions, the adoption of recommendations, the furnishing of technical assistance and the holding of regional meetings and technical meetings for the purpose of consultation and study organized in conjunction with the Governments concerned.”Footnote ¹²³

Some states have characterized these features of the ICESCR as mere political commitments, not legal obligations.Footnote ¹²⁴ However, the Committee on Economic, Social and Cultural Rights has affirmed that the Covenant’s requirements for international cooperation are legally binding. In its General Comment No. 3, the Committee has stated

This is so, the Committee observes, because “in the absence of an active programme of international assistance and cooperation on the part of all those States that are in a position to undertake one, the full realization of economic, social and cultural rights will remain an unfulfilled aspiration in many countries.”Footnote ¹²⁶ In other words, mandatory cooperation is essential to achieve the ICESCR’s object and purpose.

The Committee on the Rights of the Child has reached the same conclusion for economic, social, and cultural rights enshrined in the UN Convention on the Rights of the Child (UNCRC).Footnote ¹²⁷ Article 4 of the UNCRC requires states-parties to “undertake all appropriate legislative, administrative, and other measures for the implementation of the rights recognized in the present Convention. With regard to economic, social and cultural rights, States Parties shall undertake such measures to the maximum extent of their available resources and, where needed, within the framework of international co-operation.”Footnote ¹²⁸ “When States ratify the Convention,” the Committee explains, “they take upon themselves obligations not only to implement it within their jurisdiction but also to contribute, through international cooperation, to global implementation.”Footnote ¹²⁹

In 2011, a group of forty eminent international law experts from around the world gathered in the Netherlands to “clarify [the] extraterritorial obligations of States on the basis of standing international law.”Footnote ¹³⁰ The resulting Maastricht Principles on the Extraterritorial Obligations of States in the Area of Economic, Social and Cultural Rights (Maastricht Principles) confirms that states must cooperate in good faith to protect and fulfill economic, social, and cultural rights for those both inside and outside their territories.Footnote ¹³¹ Consistent with general principles of mandatory cooperation, the Maastricht Principles indicate that states’ cooperative obligations must be ascertained based on equitable principles, accounting for factors such as states’ respective “economic, technical and technological capacities, available resources, and influence in international decision-making processes.”Footnote ¹³² Mandatory cooperation thus gives states common but differentiated responsibilities to protect and fulfill economic, social, and cultural rights.

Mandatory Cooperation in the Real World

In the closing days of the San Francisco Conference, when negotiations over the draft Charter teetered on the brink of collapse, Truman dispatched an envoy to Moscow with instructions to “make it clear to Uncle Joe Stalin that I knew what I wanted – and that I intended to get [from the United Nations] – peace for the world for at least 90 years.”Footnote ¹³³

If perpetual peace is the standard by which the United Nations must be judged, then surely it will be found wanting. Mandatory cooperation has not saved succeeding generations from the scourge of war. Less than two months after the San Francisco Conference, Truman shocked the world by authorizing the use of nuclear weapons against Hiroshima and Nagasaki. Since World War II and the Korean War, the world has endured hundreds of devastating conflicts, including the Algerian War, the Vietnam War, the Iran-Iraq War, the Bosnian War, the Iraq War, recurring armed struggles in Afghanistan and Congo, and civil wars in Burundi, El Salvador, Guatemala, Libya, Nigeria, Sri Lanka, Somalia, Sudan, Syria, and Yemen, to name just a few. Nor has international cooperation solved the puzzle of mass atrocities. As this volume goes to print, diplomats continue to wring their hands in futility as North Korea systematically murders, rapes, and tortures detainees in prison camps;Footnote ¹³⁴ Israel continues to restrict the delivery of humanitarian aid to starving Palestinians in defiance of provisional measures indicated by the ICJ;Footnote ¹³⁵ and Russia refuses to comply with an ICC warrant to arrest Putin for war crimes.Footnote ¹³⁶ Sadly, states sometimes conspire with one another to defeat international efforts to suppress aggression and human rights abuse – including through their abuse of the P5 veto power.Footnote ¹³⁷ As long as states decline to condemn wars of territorial conquest, such as Russia’s invasion of Ukraine,Footnote ¹³⁸ it is plain that we are nowhere near the future Tennyson foresaw in which “the war-drum throbb’d no longer” and “the kindly earth shall slumber, lapt in universal law.”Footnote ¹³⁹

Still, as hard as it may be to achieve, cooperation is necessary if the international community hopes to secure sovereign equality, maintain international peace and security, and safeguard humanity from oppression. This is why the Charter enshrines mandatory cooperation as a cornerstone principle – arguably the cornerstone principle – of our international legal order.

And there is some basis for cautious (if limited) optimism. For all their shortcomings, UN peacekeeping missions have made valuable contributions to curtailing armed conflicts, reducing civilian casualties, and strengthening peace agreements, thereby saving countless lives.Footnote ¹⁴⁰ Dozens of the worst human rights abusers have been prosecuted successfully for atrocity crimes, including Mladić, who, with Serbia’s assistance, was finally tried and sentenced to life in prison for genocide by the ICTY in 2017.Footnote ¹⁴¹ Mandatory cooperation has also advanced economic, social, and cultural rights worldwide. Since 1990, international cooperation of the kind envisioned in the ICESCR has lifted more than 1.1 billion people out of extreme poverty.Footnote ¹⁴² Over fifty million lives have been saved through international cooperation to combat HIV, tuberculosis, and malaria in low- and middle-income countries.Footnote ¹⁴³ If there is a path toward a more decent and peaceful world, it runs through mandatory cooperation.