Fractional Orbital Bombardment Systems
We analyze Fractional Orbital Bombardment Systems (FOBS) as a means of delivering nuclear weapons by placing warheads into partial orbits around the Earth, and show that they do not represent a game-changing advance in technology or capability. We consider potential uses of such a weapon, including evading missile defenses and delivering attacks with short warning time. FOBS could underfly current exoatmospheric defenses, but the required payload reduction may not justify its use if other countermeasures are deemed effective. If a FOBS attack could be successfully disguised as a satellite launch, the warning time could be short enough to raise fears of a decapitating strike. The development of such a capability could lead countries to shorten decision-making timelines in a crisis, which would be destabilizing. The US can take steps to ensure that very-short-warning attacks would not succeed, thereby enhancing deterrence during a crisis.