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Autonomous weapons systems and changing norms in international relations

  • Ingvild Bode (a1) and Hendrik Huelss (a2)

Autonomous weapons systems (AWS) are emerging as key technologies of future warfare. So far, academic debate concentrates on the legal-ethical implications of AWS but these do not capture how AWS may shape norms through defining diverging standards of appropriateness in practice. In discussing AWS, the article formulates two critiques on constructivist models of norm emergence: first, constructivist approaches privilege the deliberative over the practical emergence of norms; and second, they overemphasise fundamental norms rather than also accounting for procedural norms, which we introduce in this article. Elaborating on these critiques allows us to respond to a significant gap in research: we examine how standards of procedural appropriateness emerging in the development and usage of AWS often contradict fundamental norms and public legitimacy expectations. Normative content may therefore be shaped procedurally, challenging conventional understandings of how norms are constructed and considered as relevant in International Relations. In this, we outline the contours of a research programme on the relationship of norms and AWS, arguing that AWS can have fundamental normative consequences by setting novel standards of appropriate action in international security policy.

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*Correspondence to: Ingvild Bode, School of Politics and International Relations, Rutherford College, University of Kent, Canterbury, CT2 7NX, UK. Author’s email:
**Correspondence to: Hendrik Huelss, School of Politics and International Relations, Rutherford College, University of Kent, Canterbury, CT2 7NX, UK. Author’s email:
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1 UK Ministry of Defence, ‘The UK Approach to Unmanned Aircraft Systems. Joint Doctrine Note 2/11 (JDN 2/11)’ (2011).

2 There are some notable exceptions: Altmann, Jürgen and Sauer, Frank, ‘Autonomous weapon systems and strategic stability’, Survival, 59:5 (3 September 2017), pp. 117142 ; Garcia, Denise, ‘Future arms, technologies, and international law: Preventive security governance’, European Journal of International Security, 1:1 (27 February 2016), pp. 94111 ; Carl Haas, Michael and Fischer, Sophie-Charlotte, ‘The evolution of targeted killing practices: Autonomous weapons, future conflict, and the international order’, Contemporary Security Policy, 38:2 (2017), pp. 281306 ; Shaw, Ian G. R., ‘Robot wars: US empire and geopolitics in the Robotic Age’, Security Dialogue, 48:5 (2017), pp. 451470 .

3 Heyns, Christof, ‘Autonomous weapons systems: Living a dignified life and dying a dignified death’, in Nehal Bhuta et al. (eds), Autonomous Weapons Systems: Law, Ethics, Policy (Cambridge: Cambridge University Press, 2016), pp. 320 (p. 4).

4 Heather Roff, ‘Autonomous or “Semi” Autonomous Weapons? A Distinction Without Difference’, Huffington Post blog (16 January 2015), available at: {}.

5 Ingvild Bode and Hendrik Huelss, ‘Why “Stupid” Machines Matter: Autonomous Weapons and Shifting Norms’, Bulletin of the Atomic Scientists (12 October 2017), available at: {“stupid”-machines-matter-autonomous-weapons-and-shifting-norms11189}; Toby Walsh, ‘Elon Musk Is Wrong: The AI Singularity Won’t Kill Us All’, Wired (20 September 2017), available at: {

6 Leveringhaus, Alex, Ethics and Autonomous Weapons (London: Palgrave Macmillan, 2016); Fleischman, William M., ‘Just say “no!” to lethal autonomous robotic weapons’, Journal of Information, Communication and Ethics in Society, 13:3/4 (2015), pp. 299313 ; Roff, Heather M., ‘The strategic robot problem: Lethal autonomous weapons in war’, Journal of Military Ethics, 13:3 (3 July 2014), pp. 211227 .

7 Finnemore, Martha and Toope, Stephen J., ‘Alternatives to “legalization”: Richer views of law and politics’, International Organization, 55:3 (2001), pp. 743758 .

8 Sehrawat, Vivek, ‘Autonomous weapon system: Law of armed conflict (LOAC) and other legal challenges’, Computer Law & Security Review, 33:1 (February 2017), pp. 3856 ; Kastan, Benjamin, ‘Autonomous weapons systems: a coming legal singularity’, Journal of Law, Technology & Policy, 45 (2013), pp. 4582 ; Grut, C., ‘The challenge of autonomous lethal robotics to international humanitarian law’, Journal of Conflict and Security Law, 18:1 (1 April 2013), pp. 523 ; Husby, Christian, ‘Offensive autonomous weapons: Should we be worried?’, Michigan Journal of International Law, 37 (2015); Maya Brehm, ‘Defending the Boundary: Constraints and Requirements on the Use of Autonomous Weapons Systems under International Humanitarian and Human Rights Law’, Academy Briefing No. 9 (Geneva Academy, May 2017).

9 See Huelss, Hendrik, ‘After decision-making: the operationalisation of norms in international relations’, International Theory, 9:3 (2017), pp. 381409 .

10 Finnemore, Martha and Sikkink, Kathryn, ‘International norm dynamics and political change’, International Organization, 52:4 (1998), pp. 887917 ; Risse, Thomas, Ropp, Stephen, and Sikkink, Kathryn, The Power of Human Rights: International Norms and Domestic Change (Cambridge: Cambridge University Press, 1999); Elizabeth Keck, Margaret and Sikkink, Kathryn, Activists Beyond Borders: Advocacy Networks in International Politics (Ithaca, NY: Cornell University Press, 1998); Risse, Thomas, ‘“Let’s argue!”: Communicative action in world politics’, International Organization, 54:1 (2000), pp. 139 .

11 Wiener, Antje, ‘Contested compliance: Interventions on the normative structure of world politics’, European Journal of International Relations, 10:2 (2004), pp. 189234 ; Wiener, Antje, ‘Enacting meaning-in-use: Qualitative research on norms and international relations’, Review of International Studies, 35:1 (8 January 2009), pp. 175193 ; Zimmermann, Lisbeth, ‘Same same or different? Norm diffusion between resistance, compliance, and localization in post-conflict states’, International Studies Perspectives, 17:1 (2016), pp. 98115 .

12 Tannenwald, Nina, ‘The nuclear taboo: the United States basis of and the normative nuclear non-use’, International Organization, 53:3 (1999), pp. 433468 ; Garcia, Denise, Small Arms and Security: New Emerging International Norms (Abingdon: Routledge, 2006); Lantis, Jeffrey S., Arms and Influence: US Technology Innovations and the Evolution of International Security Norms (Stanford, CA: Stanford University Press, 2016).

13 Leander, Anna, ‘Thinking tools’, in Audie Klotz and Deepa Prakesh (eds), Qualitative Methods in International Relations: A Pluralist Guide (Basingstoke: Palgrave Macmillan, 2008), pp. 1127 (p. 18).

14 Wiener, Antje, ‘Contested meanings of norms: a research framework’, Comparative European Politics, 5 (2007), p. 8 .

15 Wiener, ‘Contested compliance’.

16 See, for example, Asaro, Peter, ‘On banning autonomous weapon systems: Human rights, automation, and the dehumanization of lethal decision-making’, International Review of the Red Cross, 94:886 (2012), pp. 687709 ; Future of Life Institute, ‘Autonomous Weapons: An Open Letter from AI & Robotics Researchers’ (2015), available at: {}; Sharkey, Noel E., ‘The evitability of autonomous robot warfare’, International Review of the Red Cross, 94:886 (4 June 2012), pp. 787799 .

17 As the autonomy of weapons systems evolves along a trajectory encompassing remote-controlled systems such as drones, the article recurs on these instruments to illustrate the impact of emerging standards of appropriateness.

18 See Sparrow, Robert, ‘Robots and respect: Assessing the case against autonomous weapon systems’, Ethics & International Affairs, 30:1 (2016), p. 95 .

19 Noel Sharkey, ‘Staying in the loop: Human supervisory control of weapons’, in Bhuta et al. (eds), Autonomous Weapons Systems, pp. 23–38 (p. 23).

20 Giovanni Sartor and Andrea Omicini, ‘The autonomy of technological systems and responsibilities for their use’, in Bhuta et al. (eds), Autonomous Weapons Systems, pp. 40–57.

21 Roff, ‘Autonomous or “Semi” Autonomous Weapons?’.

22 Sharkey, Noel, ‘Saying “no!” to lethal autonomous targeting’, Journal of Military Ethics, 9:4 (December 2010), p. 377 .

23 Heyns, ‘Autonomous weapons systems’; Sharkey, ‘Staying in the loop’.

24 Williams, John, ‘Democracy and regulating autonomous weapons: Biting the bullet while missing the point?’, Global Policy, 6:3 (2015), p. 183 ; Human Rights Watch, ‘Losing Humanity: The Case Against Killer Robots’ (2012), p. 2.

25 Heyns, ‘Autonomous weapons systems’, p. 14.

26 Moyes, Richard, ‘Meaningful human control’, in Robin Geiss and Henning Lahmann (eds), Lethal Autononous Weapons Systems: Technology, Definition, Ethics, Law & Security (Berlin: Federal Foreign Office, 2016), pp. 239249 .

27 Sharkey, ‘Staying in the loop’, pp. 34–7.

28 Christof Heyns, ‘Report of the Special Rapporteur on Extrajudicial, Summary or Arbitrary Executions. A/HRC/23/47’ (Geneva, 2013), pp. 5–6.

29 Heyns, ‘Autonomous weapons systems’, p. 11.

30 For a more detailed discussion, see section entitled ‘AWS and procedural norms’.

31 See Mary Wareham, ‘Banning Killer Robots in 2017’, The Cipher Brief (2017), available at: {}.

32 Campaign to Stop Killer Robots, ‘Support Builds for New International Law on Killer Robots’ (17 November 2017), available at: {}.

33 The group calling for a ban comprises (November 2017): Algeria, Argentina, Bolivia, Brazil, Chile, Costa Rica, Cuba, Ecuador, Egypt, Ghana, Guatemala, Holy See, Iraq, Mexico, Nicaragua, Pakistan, Panama, Peru, State of Palestine, Uganda, Venezuela, and Zimbabwe.

34 Chinese Delegation to CCW, ‘The Position Paper Submitted by the Chinese Delegation to CCW 5th Review Conference’ (2016), p. 1.

35 US Department of Defense, ‘Directive 3000.09 on Autonomy in Weapon Systems’ (2012), p. 13.

36 Ibid., p. 14.

37 Mark Gubrud, ‘Semi-Autonomous and on Their Own: Killer Robots in Plato’s Cave’, Bulletin of the Atomic Scientists (12 April 2015), available at: {’s-cave8199}.

38 Roff, ‘Autonomous or “Semi” Autonomous Weapons?’.

39 UK Ministry of Defence, ‘Joint Doctrine Publication 0-30.2. Unmanned Aircraft Systems’ (2017), p. 72, available at: {}.

40 Ibid., p. 72.

41 UK Ministry of Defence, ‘The UK Approach to Unmanned Aircraft Systems. Joint Doctrine Note 2/11 (JDN 2/11)’, pp. 2–3.

42 Human Rights Watch, ‘Review of the 2012 US Policy on Autonomy in Weapons Systems: US Policy on Autonomy in Weapons Systems Is First in the World’ (2013), available at: {}.

43 Campaign to Stop Killer Robots, ‘New US Policy’ (16 April 2013), available at: {}.

44 Human Rights Watch, ‘Review of the 2012 US Policy on Autonomy in Weapons Systems’.

45 We thank an anonymous reviewer for drawing our attention to this point.

46 Mark Gubrud, ‘US Killer Robot Policy: Full Speed Ahead’, Bulletin of the Atomic Scientists (20 September 2013), available at: {}.

47 Gubrud, ‘Semi-Autonomous and on Their Own’.

48 US Department of Defense, ‘Directive 3000.09’, p. 3.

49 Gubrud, ‘US Killer Robot Policy’.

50 Dan Saxon, ‘A human touch: Autonomous weapons, DoD Directive 3000.09 and the interpretation of “appropriate levels of human judgment over the use of force”’, in Bhuta et al. (eds), Autonomous Weapons Systems, p. 185.

51 Office of Naval Research, ‘News – Autonomous Swarmboats: New Missions, Safe Harbors’ (2016), available at: {}.

52 US Department of Defense, ‘Department of Defense Announces Successful Micro-Drone Demonstration: Press Operations. Release NR-008-17’ (2017), available at: {}.

53 Ibid.

54 Franz-Stefan Gady, ‘Unmanned “killer robots”: a new weapon in the US Navy’s future arsenal? The US Navy moves unmanned drones to the top of its priorities’, The Diplomat (April 2015), available at: {}.

55 Kris Osborn, ‘The US Navy’s Sub-Hunting Drone Ship is Being Upgraded to Launch Offensive Attacks’, Business Insider (2017), available at: {}.

56 Israel Aerospace Industries, ‘HAROP’ (2017), available at: {}.

57 Thomas Gibbons-Neff, ‘Israeli-made kamikaze drone spotted in Nagorno-Karabakh conflict’, The Washington Post (2016), available at: {}.

58 Stephen Goose and Mary Wareham, ‘The growing international movement against killer robots’, Harvard International Review, 37:3 (2016), available at: {}.

59 This is based on data compiled by: Vincent Boulanin, ‘Mapping the Development of Autonomy in Weapon Systems: A Primer on Autonomy’, SIPRI Working Paper (Stockholm, 2016); Heather M. Roff and Richard Moyes, ‘Dataset. Project: Artificial Intelligence, Autonomous Weapons, and Meaningful Human Control’ (2017), available at: {}.

60 Arkin, Ronald C., ‘The case for ethical autonomy in unmanned systems’, Journal of Military Ethics, 9:4 (December 2010), pp. 332341 .

61 Michael C. Horowitz and Paul Scharre, ‘Do Killer Robots Save Lives?’, POLITICO Magazine (19 November 2014), available at: {}.

62 Roff, Heather M., ‘Lethal autonomous weapons and jus ad bellum proportionality’, Case Western Reserve Journal of International Law, 47 (2015), pp. 3752 .

63 Sparrow, ‘Robots and respect’.

64 Sharkey, ‘Saying “no!” to lethal autonomous targeting’; Sharkey, ‘The evitability of autonomous robot warfare’.

65 Walsh, J. I., ‘Political accountability and autonomous weapons’, Research & Politics, 2:4 (2015), pp. 16 .

66 Hammond, Daniel N., ‘Autonomous weapons and the problem of state accountability’, Chicago Journal of International Law, 15 (2014), pp. 652687 ; Sparrow, Robert, ‘Killer robots’, Journal of Applied Philosophy, 24:1 (February 2007), pp. 6277 ; Walsh, ‘Political accountability and autonomous weapons’.

67 Johnson, Aaron M. and Axinn, Sidney, ‘The morality of autonomous robots’, Journal of Military Ethics, 12:2 (July 2013), pp. 129141 ; Leveringhaus, Ethics and Autonomous Weapons; Sharkey, ‘Saying “no!” to lethal autonomous targeting’; Sparrow, ‘Robots and respect’.

68 Sharkey, ‘Saying “no!” to lethal autonomous targeting’; Sharkey, ‘The evitability of autonomous robot warfare’; Heyns, ‘Autonomous weapons systems’.

69 Arkin, ‘The case for ethical autonomy in unmanned systems’.

70 See Kaag, John and Kreps, Sarah, Drone Warfare (Cambridge: Polity Press, 2014).

71 Garcia, ‘Future arms, technologies, and international law’, p. 101.

72 See Warren, Aiden and Bode, Ingvild, ‘Altering the playing field: the U.S. redefinition of the use-of-force’, Contemporary Security Policy, 36:2 (4 May 2015), pp. 174199 .

73 International Committee of the Red Cross, ‘Introduction’, ICRC – Customary International Humanitarian Law (2017), available at: {}.

74 Bode, Ingvild, ‘“Manifestly failing” and “unable or unwilling” as intervention formulas: a critical analysis’, in Aiden Warren and Damian Grenfell (eds), Rethinking Humanitarian Intervention in the 21st Century (Edinburgh: Edinburgh University Press, 2017), pp. 164191 .

75 See Ingvild Bode, ‘How the World’s Interventions in Syria Have Normalised the Use of Force’, The Conversation (17 February 2016), available at: {}.

76 Wayne McLean, ‘Drones Are Cheap, Soldiers Are Not: A Cost-Benefit Analysis of War’, The Conversation (2014), available at: {; Michael W. Lewis, ‘Drones: Actually the Most Humane Form of Warfare Ever’, The Atlantic (2013), available at: {}.

77 Sauer, Frank and Schörnig, Niklas, ‘Killer drones: the “silver bullet” of democratic warfare?’, Security Dialogue, 43:4 (August 2012), p. 375 .

78 Fairleigh Dickinson University, ‘Public Says It’s Illegal to Target Americans Abroad as Some Question CIA Drone Attacks’ (2013), p. 1, available at: {}.

79 Singer, Peter W., Wired for War: The Robotics Revolution and Conflict in the 21st Century (New York: Penguin, 2010).

80 Wiener, ‘Enacting meaning-in-use’.

81 Finnemore and Sikkink, ‘International norm dynamics and political change’; Keck and Sikkink, Activists Beyond Borders; Risse, Ropp, and Sikkink, The Power of Human Rights; Risse, ‘“Let’s argue!”’.

82 Tannenwald, ‘The nuclear taboo’; Jefferson, Catherine, ‘Origins of the norm against chemical weapons’, International Affairs, 90:3 (May 2014), pp. 647661 .

83 Tannenwald, ‘The nuclear taboo’, p. 436.

84 Keck and Sikkink, Activists Beyond Borders; Risse, Ropp, and Sikkink, The Power of Human Rights.

85 Finnemore and Sikkink, ‘International norm dynamics and political change’, p. 895.

86 Garcia, Small Arms and Security.

87 Wiener, Antje, A Theory of Contestation (Berlin: Springer, 2014); Bloomfield, Alan, ‘Norm antipreneurs and theorising resistance to normative change’, Review of International Studies, 42:2 (2016), pp. 310333 ; Zimmermann, ‘Same same or different?’.

88 Wiener, ‘Contested compliance’.

89 Tannenwald, ‘The nuclear taboo’; Jefferson, ‘Origins of the norm against chemical weapons’; Rosert, Elvira et al., ‘Arms control norms and technology’, in Harald Müller and Carmen Wunderlich (eds), Norm Dynamics in Multilateral Arms Control: Interests, Conflicts, and Justice, Studies in Security and International Affairs (Athens, GA: University of Georgia Press, 2013).

90 Kütt, Moritz and Steffek, Jens, ‘Comprehensive prohibition of nuclear weapons: an emerging international norm?’, The Nonproliferation Review, 22:3–4 (2 October 2015), p. 403 .

91 Wallach, Wendell and Allen, Colin, ‘Framing robot arms control’, Ethics and Information Technology, 15:2 (21 June 2013), pp. 125135 (p. 125).

92 Based on Wiener, ‘Enacting meaning-in-use’, p. 184.

93 Asaro, Peter, ‘How just could a robot war be?’, in Adam Briggle, Katinka Waelbers, and Philip Brey (eds), Current Issues in Computing and Philosophy, Frontiers in Artificial Intelligence and Applications (Amsterdam, Netherlands ; Washington, DC: IOS Press, 2008), pp. 115 .

94 March, James G. and Olsen, Johan P., Rediscovering Institutions: The Organizational Basis of Politics (New York: Free Press, 1989).

95 Wiener, ‘Enacting meaning-in-use’, p. 184.

96 Bueger, Christian and Gadinger, Frank, ‘The play of international practice’, International Studies Quarterly, 59 (2015), pp. 449460 ; Bueger, Christian and Gadinger, Frank, International Practice Theory (Basingstoke: Palgrave Macmillan, 2014).

97 Leander, ‘Thinking tools’.

98 Ingvild Bode, ‘Reflective practices at the Security Council: Children and armed conflict and the three United Nations’, European Journal of International Relations (2017), Online First, p. 2, available at: {doi: 10.1177/1354066117714529}.

99 Leander, Anna, ‘Technological agency in the co-constitution of legal expertise and the US drone program’, Leiden Journal of International Law, 26:4 (8 December 2013), p. 813 .

100 Schwarz, E., ‘Prescription drones: On the techno-biopolitical regimes of contemporary “ethical killing”‘, Security Dialogue, 47:1 (1 February 2016), p. 65 .

101 Best, Jacqueline and Walters, William, ‘“Actor-network theory” and international relationality: Lost (and found) in translation’, International Political Sociology, 7:3 (12 September 2013), pp. 332334 ; see Callon, Michel, ‘Some elements of a sociology of translation: Domestication of the scallops and the fishermen of St Brieuc Bay’, The Sociological Review, 32 (May 1984), pp. 196233 ; Leander, ‘Technological agency’.

102 Noone, Gregory P. and Noone, Diane C., ‘The debate over autonomous weapons systems’, Case Western Reserve Journal of International Law, 47 (2015), p. 33 ; Haas and Fischer, ‘The evolution of targeted killing’, p. 295.

103 See Sparrow, ‘Robots and respect’, p. 96; Horowitz, Michael C., Kreps, Sarah E., and Fuhrmann, Matthew, ‘Separating fact from fiction in the debate over drone proliferation’, International Security, 41:2 (October 2016), p. 26 .

104 Adams, Thomas K., ‘Future warfare and the decline of human decisionmaking’, Parameters, 31:4 (2001), p. 1 .

105 Garcia, Denise, ‘Killer robots: Why the US should lead the ban’, Global Policy, 6:1 (February 2015), pp. 5763 .

106 UK Ministry of Defence, ‘The UK Approach to Unmanned Aircraft Systems’, Conclusion, p. 1.

107 Gubrud, ‘US Killer Robot Policy’.

108 Neta C. Crawford, ‘US Budgetary Costs of Wars through 2016: $4.79 Trillion and Counting. Summary of Costs of the US Wars in Iraq, Syria, Afghanistan and Pakistan and Homeland Security’ (Costs of War Project. Watson Institute of International and Public Affairs. Brown University, September 2016), pp. 2–3.

109 Horowitz, M. C., ‘Public opinion and the politics of the killer robots debate’, Research & Politics, 3:1 (16 February 2016), pp. 18 .

110 Kurzweil, Ray, The Age of Spiritual Machines: When Computers Exceed Human Intelligence (New York, NY: Penguin, 2000).

111 Marchant, Gary E. et al., ‘International governance of autonomous military robots’, The Columbia Science and Technology Law Review, XII (2011), p. 284 .

112 Sharkey, ‘The evitability of autonomous robot warfare’; Sharkey, ‘Saying “no!” to lethal autonomous targeting’.

113 Gubrud, ‘US Killer Robot Policy’.

114 Watts, Barry D., ‘Six Decades of Guided Munitions and Battle Networks: Progress and Prospects’ (Centre for Strategic and Budgetary Assessments, March 2007), p. 283 .

115 Heyns, ‘A/HRC/23/47’; Sharkey, ‘Staying in the loop’.

116 Paul Aksenov, ‘Stanislav Petrov: the man who may have saved the world’, BBC Russian (26 September 2013), available at: {}.

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