- In full:
- Treaty on the Limitation of Anti-Ballistic Missile Systems
- Date:
- 1972
- Participants:
- Soviet Union
- United States
Anti-Ballistic Missile Treaty
-
What was the Anti-Ballistic Missile (ABM) Treaty?
The Anti-Ballistic Missile Treaty (ABM Treaty), an arms control treaty, was ratified in 1972 between the United States and the Soviet Union. It aimed to limit the deployment of missile systems capable of destroying incoming intercontinental ballistic missiles (ICBMs).
The treaty originally limited each side to two ABM deployment areas with 100 launch systems and interceptor missiles each. A 1974 protocol reduced this to one ABM site apiece.
In December 2001, President George W. Bush gave notice of the abrogation of the ABM treaty, marking the first time the U.S. had withdrawn from a major arms control agreement.
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Which countries signed the ABM Treaty, and when did it happen?
The Anti-Ballistic Missile (ABM) Treaty was signed in Moscow in May 1972 by U.S. President Richard Nixon and Soviet leader Leonid Brezhnev. It was then ratified by both the U.S. Senate and the Supreme Soviet later that year.
The treaty sought to limit the deployment of missile systems that could theoretically destroy incoming intercontinental ballistic missiles (ICBMs). It restricted each side to two ABM deployment areas with no more than 100 launch systems and 100 interceptor missiles at each site. A 1974 protocol further reduced this to one ABM site apiece.
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What is an anti-ballistic missile, and what does it do?
An anti-ballistic missile (ABM) is a weapon designed to intercept and destroy ballistic missiles. The United States and the Soviet Union developed ABM systems during the Cold War. The Anti-Ballistic Missile Treaty of 1972 limited both sides to two ABM deployment areas. In 2002, the U.S. withdrew from the treaty to develop defenses against limited missile attacks by smaller powers.
ABM systems use radar to detect, track, and engage incoming warheads, distinguishing them from decoys and other objects. Engagement can occur outside the atmosphere (exoatmospheric) for long-range defense or within the atmosphere (endoatmospheric), which offers a smaller defended area.
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Why did the United States and the Soviet Union agree to limit anti-ballistic missile systems?
The United States and the Soviet Union agreed to limit anti-ballistic missile (ABM) systems due to the concept of mutual assured destruction (MAD). Each side recognized that neither could develop a defense that would prevent unacceptable damage from a nuclear attack.
The ABM Treaty, ratified in 1972, limited each side to two ABM deployment areas to protect the national capital and an ICBM launch site. A 1974 protocol further reduced this to one ABM site apiece. By limiting ABM systems, both countries remained vulnerable to each other's strategic forces, reinforcing MAD, where the threat of annihilation would deter either side from initiating a nuclear conflict.
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How did the ABM Treaty affect the nuclear arms race during the Cold War?
The Anti-Ballistic Missile (ABM) Treaty, ratified in 1972 by the United States and the Soviet Union, aimed to limit the deployment of missile systems that could theoretically destroy incoming intercontinental ballistic missiles (ICBMs).
By banning nationwide antiballistic missile systems, the treaty confirmed the primacy of offensive weapons, reinforcing the concept of mutual assured destruction (MAD). Under MAD, both sides were deterred from initiating a nuclear attack due to the certainty of devastating retaliation. Though controversial, MAD created a more stable relationship between the two superpowers.
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What happened to the ABM Treaty after the Cold War ended?
After the Cold War, the Anti-Ballistic Missile (ABM) Treaty faced new challenges with the emergence of potential missile attacks from "rogue" states. Although the treaty was originally designed to limit large-scale missile systems between the United States and the Soviet Union, the U.S. proposed a National Missile Defense (NMD) system in the 1990s to counter smaller-scale threats.
In December 2001, President George W. Bush withdrew from the ABM Treaty, describing it as a relic of the Cold War era. This marked the first time the U.S. had withdrawn from a major arms control agreement, a move Russia called a mistake.
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Anti-Ballistic Missile Treaty (ABM Treaty), arms control treaty ratified in 1972 between the United States and the Soviet Union to limit deployment of missile systems that could theoretically be used to destroy incoming intercontinental ballistic missiles (ICBMs) launched by the other superpower. Negotiations to prohibit ballistic missile defenses were first proposed by the United States in 1966 but did not begin until late 1969, as part of the Strategic Arms Limitation Talks (SALT). The ABM Treaty was signed by U.S. Pres. Richard Nixon and Soviet leader Leonid Brezhnev at a summit in Moscow in May 1972, and it was ratified by both the U.S. Senate and the Supreme Soviet later that year.
The ABM treaty limited each side to only two ABM deployment areas, one to protect the national capital and another to protect an ICBM launch site, with each ABM deployment area limited to 100 launch systems and 100 interceptor missiles. A 1974 protocol reduced the agreement to one ABM site apiece. The Soviet Union opted to maintain an established system protecting Moscow; it was upgraded in the 1980s and is said to be still operational. The United States opted to protect an ICBM site at Grand Forks, N.D., although the system deployed was decommissioned in 1976. To prevent the deployment of a nationwide battle management system, the treaty required all early-warning radars (usually large phased-array radars) to be sited on the periphery of the country, oriented outward. In 1984 the United States claimed that a Soviet radar system near the city of Krasnoyarsk, 800 km (500 miles) from the nearest border, violated this provision, and in 1989 the Soviets acknowledged the violation and agreed to dismantle the radar. In addition to traditional interceptor missiles, launchers, and radars, the ABM treaty also covers systems based on other principles, such as lasers.
Under the terms of the treaty, neither party was able to defend more than a small fraction of its entire territory, and both sides were thus kept subject to the deterrent effect of the other’s strategic forces. This arrangement was seen to reinforce the concept of mutual assured destruction (MAD), in which the prospect of annihilation for both sides would prevent either side from “going nuclear” in the event of a conflict. The very concept of MAD was controversial, however. During the 1980s, U.S. Pres. Ronald Reagan promoted his Strategic Defense Initiative (also known as Star Wars), based on an alternative concept of assured survival. Technology existing at the time did not support this ambitious goal, though, and in any case the end of the Cold War significantly lowered the risk of a massive nuclear exchange. During the course of the 1990s, attention turned to the risk of small-scale missile attacks from so-called “rogue” states, such as North Korea or Iraq. With this in mind, a National Missile Defense (NMD) system was proposed in the United States. Although it would involve no more than 100 interceptors, it was a system designed to provide nationwide defense and so would be inconsistent with the ABM treaty. For this reason, Russia publicly opposed the NMD. In order to mollify the Russians, the administration of U.S. Pres. Bill Clinton explored amending the ABM treaty during the 1990s to permit the deployment of limited defenses that would clearly not be able to blunt a Russian attack. The administration of U.S. Pres. George W. Bush, however, saw no merit in trying to preserve a treaty that it described as a “relic” of the Cold War era, and in December 2001 Bush gave the required six-months notice of abrogation of the ABM treaty, which was the first time that the United States had withdrawn from a major arms control agreement. Russia did no more than describe this action as “mistaken.”
