The land domain: Unmanned ground vehicles (UGVs); Remote operation of existing vehicles; Future unmanned ground systems; Unmanned maritime systems: Underwater vehicles; Problems with the system; Unmanned surface vehicles; Beyond the West; Military aerospace: Technology uptake; Contested environments


In recent years the use of unmanned systems has been given increased attention by armed forces, defence ministries, defence industry, analysts and the media. The most visible capability in this area has been the unmanned aerial vehicle (UAV), attracting particular public interest because of the integration of weapons systems and the use of some platforms as strike assets in locations such as Pakistan. However, unmanned systems are making inroads into all services’ inventories, in an expanding number of roles, and will also be increasingly utilised by law-enforcement agencies. The proliferation of smaller systems – particularly, but not exclusively, in the air domain – has reduced costs and barriers to entry (in terms of the technological capacity needed to operate and benefit from such systems), enabling greater use by private companies, individuals and countries possessing limited financial resources.

Legal and ethical debates have been stimulated by the state use of all forms of unmanned systems. However, the proliferation and visibility of UAVs, and their use by armed forces and government agencies, has led to these platforms dominating the debate. A range of issues have been raised; from whether attacks can be justified as self-defence by the prosecuting state, and whether they constitute a proportionate response, to the combatant – or otherwise – status of targeted individuals. These and related concerns now occupy justice and defence ministry legal departments, and animate a wider debate among jurists, defence professionals and the interested public.

Defence policymakers are also forced to consider other questions about the use of force more broadly, including whether use of unmanned systems could alter the political cost of warfare; whether state intervention becomes easier by employing them; and whether there could be greater deployment due to perceived force protection and ‘increased persistence’ benefits (particularly for surveillance platforms).

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