Abstract
The legal status of unmanned maritime systems is unsettled. Whereas this does not pose insurmountable problems in times of peace, it could prove as an obstacle to the use of unmanned maritime systems for the exercise of belligerent rights in times of international armed conflict. Nevertheless, unmanned maritime systems will qualify as means of warfare, if they are used for attack purposes. While they are not unlawful per se, even if semi-autonomous or autonomous, their use will have to be in compliance with targeting law.