Like traditional activities in the domains of land, sea and air, activities in the domain of outer space can affect the peace and security of the international community on Earth. Left unchecked, current freedoms on the use of outer space may permit space-faring nations to place weapons there for the sole purpose of enhancing their individual national security interests. Outer space has not yet witnessed the introduction of space-based weapons on a permanent basis, but this "weapon-free" status may change if the international community does not first prevent space weaponization through the timely negotiation of measures banning the introduction of weapons into outer space. For the purpose of this discussion, "weaponization" is limited to destructive mechanisms and do not include observation, communications or other non-destructive activities, even if military in nature.

 

The weaponization of space could take a variety of forms. First, there is the threat from above posed by space strike or orbital bombardment weapon systems. Orbital bombardment weapons are weapon systems that operate in space for one or more orbits and strike at land, sea or air targets. Secondly, there are anti-satellite (ASAT) weapon systems used to permanently degrade, damage or destroy enemy satellites. Lastly, there are ballistic missile defense (BMD) weapon systems. Some variants of BMD systems may be based in outer space and be used to destroy incoming ballistic missiles through the boost and mid-course phases of their flight. Putative weapons, such as orbiting space-based lasers based on "exotic" technologies or variants of conventionally-armed and kinetic energy "kill- mechanism" missile interceptors may be capable of performing all three functions.

 

The development, testing and deployment of space-based anti-satellite and ballistic missile defense systems, in addition to threatening the current peaceful uses of outer space, could also extinguish the explicit right of use of outer space of any nation in favor of implicit permission for its use by the first nation to successfully deploy such weapons in outer space. Access to outer space via space launch vehicles might then need to run a gauntlet of orbiting space-based weapons. Given the immense value of outer space for the economic benefit of the international community and the maintenance of international peace and security, not to mention the vast wealth of extraterrestrial resources, other nations might then accelerate research and development of Earth-based and space-based technologies designed to break this monopoly on weaponization. This could precipitate an arms race in outer space.