National Missile Defense

US programme to create a system to defend the USA against a limited strategic ballistic missile attack. NMD is a much reduced version of the Strategic Defense Initiative (SDI). It involves launching interceptor missiles from the ground, using land-based radars and space-based infrared sensors to guide them to destroy incoming long-range missiles. The NMD initiative is overseen by the Ballistic Missile Defense Organization (BMDO), set up in 1993.

Since the end of the Cold War, the main threat to the USA is felt to come from nations such as Iran, Iraq, and North Korea, which are soon likely to have the potential to hit US targets with nuclear missiles. The system also aims to protect against a small accidental or unauthorised launch of strategic-ballistic missiles from nuclear capable states.

The launch of a rocket by North Korea in August 1998 led to an increase in funding for the NMD. However, in September 2000, following the failure of the exoatmospheric kill vehicle (EKV) to hit its target in two of the first three tests, President Bill Clinton deferred a decision on deployment. President George W Bush supports early deployment, once a reliable system has been developed. NMD's deployment would breach the 1972 US-Russian Anti-Ballistic Missile (ABM) treaty, under which the USA and the Soviet Union agreed that neither would build a comprehensive defence against the other's long-range nuclear arsenal.

NMD initially received a quarter of the BMDO's annual funding - US$3 billion over five years - the remainder going chiefly to Theater Missile Defense (TMD), based around the army's Patriot and navy's Aegis missile systems. Since 1995 the relative importance of NMD has increased, due to Republicans gaining control of Congress and military intelligence reports warning of the imminent nuclear capability of smaller states. In January 1999, US Defense Secretary William Cohen added US$6.6 billion to the NMD programme.

NMD is fiercely opposed by Russia and China. In response to President Bush's enthusiastic revival of the project in 2001, Russia proposed an alternative missile defence system, based on close cooperation between Europe, Russia, and the USA. It would have an early warning system and interceptor missiles sited close to sources of threat.

Critics point out that NMD is not necessarily cost effective. It will cost an estimated US$27 billion over 20 years for a single interceptor site plus radars, but NMD remains vulnerable to development of counter-measure, including sophisticated decoys. It is also risky as it does not guarantee total security from even a minor nuclear attack: the US Defense Department having set the goal for an NMD system destruction of 95% of incoming missiles.

Israel has built a reduced version of NMD, with US financial help: the Arrow Weapon System. The system intercepts an enemy missile in the upper atmosphere (not in space), and became operational in 2001.