There are no international norms or policies that explicitly limit the use of space weapons. These weapons are not subject to international laws. This can cause confusion and lead to conflict. The United States has rejected an international treaty restricting the use of these weapons. Russia has also rejected it.
International legal instruments that exist don't limit space weapons explicitly
As space systems continue to play an increasing role in war and international security, militaries will likely develop the means to attack or destroy them during a conflict. Many countries are investing in missile defense capabilities that could potentially be used as antisatellite weaponry. Israel has suggested that the Arrow system might be used to achieve this goal in the near future. This problem of missile defense and satellite weapons getting in the way is a serious one.
While the Outer Space Treaty does not allow WMD to be deployed and used in space orbits, it does not ban conventional space weapons or nuclear-powered missiles being launched into space. It does not prohibit conventional space weapons equipped with nuclear power sources. It is not clear what rules apply to intercontinental ballistic space missiles.
The U.S. refuses to sign a treaty that would limit them
Russia and China submitted to the United Nations a draft of a treaty that would limit the use space weapons. However, the United States refuses to sign it due to concerns about space weapons' secretive nature. Bush's administration dismissed the treaty in diplomatic terms. The Obama administration is also reluctant to sign the treaty.
While the United Nations has agreed to prevent an outer space arms race, it has not negotiated an effective treaty to limit space weapons. The United States claims that because there is no such race there is no need for action. However, the international community agrees with the United States that space weaponization must be stopped.
The treaty would require all states to conduct legal reviews of any space weapon prior to its use. The review would check if the weapon breaches the laws or principles of weapons law. The treaty does not require the states to make their legal review public, however.
Russia
There has been much controversy in the past couple of years about whether Russia has space weapons. Although there are many theories, some commentators believe Russia is creating space weapons to counter the aggressive US space weapons program. One Russian commentator stated that the program would deter hostile actions with space-enabled weaponry.
The Russians are testing their capabilities with anti-satellite weapons. These weapons use radars and aircraft to strike satellites. Russia is also working on a way to shoot down another satellite with one of its own. This is no surprise given our dependence upon satellites. Many countries have called for a treaty that would prevent the creation of space weapons.
Russia's space program is a vital part of its national security. It is vital for Moscow's nuclear forces. Its early warning satellites are capable of monitoring objects in low-Earth orbits and providing launch data to command-and control centers.