Since the first V2 rockets rained down on London during World War II, countries have sought, in fits and spurts, a defense against missile attack. The U.S.-Soviet nuclear and missile arms race increased the threat. Over the years, various schemes for national missile defense were developed and discarded as unworkable against thousands of sophisticated long-range missiles.
In 1983, President Reagan revived missile defense research efforts with the visionary goal of rendering nuclear weapons “impotent and obsolete.” His Strategic Defense Initiative revived research on various missile interceptor technologies.
At the October 1986 Reykjavik summit with Soviet leader Mikhail Gorbachev, Reagan suggested that both countries abandon “mutual assured destruction” by agreeing to eliminate all offensive ballistic missiles within 10 years while researching and jointly developing strategic missile defenses.
Although Gorbachev rejected Reagan’s proposal, the meeting set the stage for the 1987 Intermediate-Range Nuclear Forces (INF) Treaty, which scrapped all of their ground-launched missiles with ranges between 500 and 5,500 kilometers and eased Cold War tensions.
Reagan also began talks toward the 1991 Strategic Arms Reduction Treaty (START), the first treaty to verifiably reduce strategic nuclear weapons. Under START, U.S. and Russian deployed strategic arsenals shrank from over 10,000 warheads each to less than 2,500 each.
Because potential foes can counter missile defense by building enough offensive ballistic missiles to overwhelm the system, the Reagan administration also established the Missile Technology Control Regime in 1987 to help curb the spread of technologies related to missiles capable of carrying nuclear, chemical, and biological warheads. MTCR membership has grown and has contributed to constraining or ending missile programs in several countries.
Today, 32 states possess ballistic missiles, but only 10 states have produced or flight-tested missiles with ranges exceeding 1,000 kilometers. For now, China and Russia are the only two states that have a proven capability to launch ballistic missiles from their territories that can strike the United States.
With the collapse of the Soviet Union and easing of the superpower nuclear rivalry, the focus of U.S. missile defense efforts shifted to responding to more limited attacks and the threat of shorter-range missiles from states such as North Korea and Iran.
Over the years, various U.S. missile defense systems have been fielded, primarily to counter short and medium-range missile threats, such as the Patriot and Theater High Altitude Area Defense (THAAD) systems. After many years of research, in 2004 the George W. Bush administration deployed 30 ground-based strategic missile interceptors in Alaska and California.
In 2009, the Obama administration modified the Bush administration’s plan for deploying strategic interceptors in Europe in favor of the European Phased Adaptive Approach. The Phased Approach involves the deployment of hundreds of more effective Standard Missile-3 (SM-3) interceptors on Aegis ships in the Mediterranean Sea and on land in Romania and Poland, with a radar in southeastern Europe to counter Iranian short- and medium-range missiles, and, if necessary, against long-range missiles after 2018.
Although President Reagan was unable to conclude a deal to cooperate on missile defense with the Soviet Union, President George W. Bush renewed efforts in this area with Russia in part to assure Russia that U.S. missile defenses are not intended to undermine Russian security. In 2004, the Bush administration began seeking a Defense Technical Cooperation Agreement (DTCA) with Russia that would have addressed a broad range of cooperative research and development activities, including missile defense.
The Obama administration and NATO allies are now continuing talks with Russia to provide a basis for cooperation on missile defenses, including the sharing of early-warning data regarding missile launches by other states, which could improve U.S., NATO, and Russian capabilities to detect and respond to Iranian missile launches.