States have presented a range of arguments against the expansion of human rights law into the extra-territorial military sphere. This article focuses on one argument in particular – the ‘deterrent argument’. This is the idea that if States are expected to uphold human rights obligations during extra-territorial military operations, it will deter them from contributing troops to UN peace support missions, which would naturally include those sanctioned under the Responsibility to Protect doctrine. This article considers how the ECtHR’s jurisprudence could actually apply to such military operations in practice and whether States should logically be deterred from participating in such missions. We argue that the involvement of the UN and the types of missions undertaken under R2P should not deter States from participation, but rather that UN involvement neutralises or mitigates many of the negative issues States fear in this area, reducing the likelihood of human rights liability for States.