Antiballistic

An anti-ballistic missile (ABM) is a surface-to-air missile designed to counter ballistic missiles (see missile defense). Ballistic missiles are used to deliver nuclear, chemical, biological or conventional warheads in a ballistic flight trajectory. The term "anti-ballistic missile" is a generic term conveying a system designed to intercept and destroy any type of ballistic threat, however it is commonly used for systems specifically designed to counter intercontinental ballistic missiles (ICBMs).

There are only two systems in the world that can intercept ICBMs. Besides them, many smaller systems exist (tactical ABMs), that generally cannot intercept intercontinental strategic missiles, even if within range—an incoming ICBM simply moves too fast for these systems.

The Russian A-35 anti-ballistic missile system, used for the defense of Moscow, whose development started in 1971. The currently active system is called A-135. The system uses Gorgon and Gazelle missiles with nuclear warheads to intercept incoming ICBMs.

The U.S. Ground-Based Midcourse Defense (GMD; previously known as National Missile Defense – NMD) system has reached initial operational capability. Instead of using an explosive charge, it launches a kinetic projectile. The George W. Bush administration accelerated development and deployment of a system proposed in 1998 by the Clinton administration. The system is a dual purpose test and interception facility in Alaska, and in 2006 was operational with a few interceptor missiles. The Alaska site provides more protection against the nuclear threat from North Korean missiles or launches from Russia or China, but is likely less effective against missiles launched from the Middle East. President Bush referenced the September 11 attacks in 2001 and the proliferation of ballistic missiles as reasons for missile defense. The current GMD system has the more limited goal of shielding against a limited attack by a rogue state such as North Korea.

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