Attività di impiego e di testing di armi anti-satellite e diritto internazionale

Anti-satellite weapons (ASAT) are one of the major challenges to international security in the «Fourth Domain», namely outer space. This was proved by the test made by Russia in November 2021 and the reaction of the international community. The present testing of said arms against its own satellites, as well as the future and probable operating use of said arms against satellites of other States, raises the problem of their compatibility with international law. In particular, it is being debated in various international fora the legality of ASATs, whose use can generate space debris further congesting terrestrial orbits, thus interfering (and jeopardizing) the activities of other States. The article concentrates on the existing rules of space law (jus ad bellum), (jus in bello) and environmental law in order to define the limits imposed on such activities. Then the author reviews the very recent phenomenon of unilateral declarations, by some States, of renunciation to test direct-ascent, kinetic ASAT, in order to assess if such renunciation may constitute the embryo of evolving customary law.