US Confirms Deployment of On-Orbit Space Control Weapons

The Outer Space Treaty (1967) remains the foundational legal instrument governing military activity in orbit. Its Article IV bans only the placement of nuclear weapons and other weapons of mass destruction in orbit or on celestial bodies. It does not prohibit conventional weapons in space. Article III requires that all space activities comply with international law, and Article IX obliges states to carry out space activities with due regard for the interests of other states, avoiding harmful interference. Attempts to close this gap through binding instruments, such as the Russia-China backed Prevention of the Placement of Weapons in Outer Space Treaty (PPWT) proposal and wider PAROS discussions at the UN Conference on Disarmament, have repeatedly stalled. Major powers disagree on what counts as a weapon and how compliance could be verified.

The history of anti-satellite testing shows how this gap has been used in practice. The United States and the Soviet Union tested ASAT weapons decades ago, China's 2007 ASAT test generated a large amount of orbital debris, and India demonstrated its own capability through Mission Shakti in 2019. The Fractional Orbital Bombardment System (FOBS) illustrates the deeper legal problem well. FOBS places a warhead into a stable low-earth orbit that later deorbits onto a target, evading conventional missile-warning systems. Because the treaty bans only WMDs and not the orbital delivery method itself, a system like FOBS sits in a contested space between what is explicitly forbidden and what is merely regulated by vague behavioural norms.