The use of military force abroad is a significant part of some states’ counter-terrorist efforts. Can these operations be ethically justified? This paper considers whether the underlying principles that philosophers have put forward to justify humanitarian interventions (which may underlie the international norm of the responsibility to protect (R2P)) can also give support for foreign counter-terrorist interventions of this sort. While it finds that the limits to international action that are imposed by the need to respect state sovereignty do not (...) rule out counter-terrorist interventions, it urges caution in supporting an international norm permitting them. Because such a norm would be open to manipulation and abuse, it may be preferable to discourage appealing to it in order to justify military counter-terrorism. (shrink)