Large nations do not like calling for outside intervention, whether diplomatic or military, to help in dealing with conflict within their own sphere of influence, let alone within their own sovereign boundaries. No country has demonstrated that more clearly than the UK, which until 1994 rejected internationalizing its peace effort in relation to the long-standing Irish conflict.

Many nations also guard zealously that provision in the UN Charter which ensures the ‘inherent right of individual or collective self-defence’, and the limitation in Article 2.7 of the UN Charter which states that ‘nothing contained in the present Charter shall authorise the United Nations to intervene in matters which are essentially within the jurisdiction of any state’. Yet while this UN wording has undoubtedly inhibited international intervention in the past, it has not prevented it. In the early 1990s, after the end of the Cold War, the balance shifted subtly in the Security Council in favour of some forms of international humanitarian intervention, both diplomatic and military. But Russia, and particularly China, had deep reservations. The onus of proof for any external intervention in an internal conflict was still on those who wished to intervene.

The humanitarian duty to intervene, or, as the French say, devoir d'ingérence, was given legitimacy under the UN Charter when on 5 April 1991 the UN Security Council passed Resolution 688, strongly advocated by the then British Prime Minister, John Major, to deal with the Kurdish refugee crisis caused by the military action of the Iraqi government.