During the administration of President Ronald Reagan, a research and development program, initiated to build a space-based antiballistic missile defense system. The Strategic Defense Initiative (SDI) program sought to end the threat of nuclear missiles through a perfect, space-based defense, but it was fraught with political and scientific difficulties.
SDI became known by the moniker Star Wars after President Reagan’s March 1983 speech declaring the U.S. ambition to make nuclear weapons “impotent and obsolete” through space-based laser interceptors. The ambitious SDI concept originally entailed the use of high-powered X-ray lasers to shoot down enemy missiles. Such lasers required an enormous amount of energy to produce, so much so that the use of atomic energy was considered the only feasible energy source.
Initial estimates for the power required to instantly destroy warheads ranged from 100 to 1,000 megawatts for up to 2,000 seconds, comparable to the power generated hourly by a nuclear power plant. Later designs incorporated the use of kinetic weapons or missiles to hit incoming missiles. Last resort ground-based interceptors were also designed. In discussion with Ronald Reagan, Edward Teller, who along with Richard Garwin is credited with the creation of the hydrogen bomb, advocated the use of X-ray lasers as interceptors to shoot down incoming missiles. Teller’s vision convinced Reagan that such a system was both feasible and highly desirable.
Critics maintained that SDI was technically unworkable and that it would alter the balance of power that had kept the world’s superpowers in check. Many scientists argued that with cheap technologies, such as multiple dummy warheads, an opponent could easily overwhelm a missile defense space weapon, thwarting the weapon’s capacity to respond to real danger. Cruise missiles, which do not enter space, and unmanned planes were also of concern.
Treaties would also have had to be renegotiated if SDI was implemented. The Antiballistic Missile Treaty held the United States and the Soviet Union to a small number of ground-based missile defenses. Signed by the United States and the Soviet Union in 1972, the ABM treaty constrained the antimissile defenses of each country to two fixed, ground-based defenses of 100 missile interceptors each. Concerns that a nationwide defense system would spur a renewed arms race caused the Soviet Union and the United States to reduce the number by half.
Both sides reasoned that a nuclear first-strike policy was unacceptable and that ultimately, remaining vulnerable to each other’s offensive nuclear weapons, while maintaining a policy aimed at deterrence, was the lesser of two evils. The Outer Space Treaty of 1967 also prohibited the deployment of space-based nuclear weapons, and so tests of such weapons could not be carried out without pulling out of the treaty.
In response to U.S. research, the Soviet Union began work on its own version of SDI. Some experts now reason that the enormous financial burden placed on the Soviet Union due to SDI helped speed the downfall of communism, and so the indirect benefit of SDI was that the United States outspent the Soviets in an economic war.
Work on SDI was discontinued after the end of the Cold War and the breakup of the Soviet Union, although research into ground-based interceptors continued. Under the Reagan administration, actual expenditures on SDI amounted to approximately $30 billion. During the administration of President Bill Clinton, missile defense received continued funding under what some dubbed the Son of Star Wars program, or National Missile Defense (NMD).
With the apparent demise of the ABM treaty, the administration of President George W. Bush is funding the development of the less-costly NMD system. Such a system, if successful, would be deployed at several locations throughout the United States and, potentially, in allied countries. As of 2004, a defense system that employs early warning radar and consists of 10 missiles to intercept nuclear ballistic missiles had been deployed in Alaska. Additionally, another 10 missiles will be deployed in California, and by the end of 2005, 10 more will be placed in Alaska.
The goal of the NMD system is what is known as layered defense, which would provide multiple opportunities to shoot down an enemy missile along its entire flight path. Ballistic missiles can be attacked in any of four phases—the boost phase, postboost phase, midcourse phase, and terminal phase. During the boost phases, missiles are at their most vulnerable. However, attacking a missile at the boost phase poses daunting challenges. First and foremost, the threat must be detected within moments.
Another antiballistic missile technology under development is the airborne laser, which is currently conceived of as a fleet of 747s outfitted with chemical lasers that would be deployed in 2008 or 2009. Adding another layer to the defense will be the Kinetic Energy Interceptor program. This initiative is aimed at deploying a boost-phase intercept capability by the year 2008. The concept of using unmanned aerial vehicles (UAVs) to counter ballistic missiles during their boost phase is also being considered.
Unlike the huge numbers of missiles that SDI would have had to field, the primary mission of National Missile Defense is the defense of the United States against a limited strategic threat, such as that posed by a rogue nation or terrorist organization. Critics maintain that the cost (currently at more than $8 billion per year) is too high and that the risk of missile attack is too low to justify NMD’s continued development.
A recent report by a team of economists found that the cumulative cost of a missile defense system—including boost-phase, midcourse, and terminal defenses as called for by the Bush administration—could be between $800 billion and $1.2 trillion. According to the Center for Defense Information, over $100 billion has been spent on SDI and NMD since President Reagan first advanced the program.
As with SDI, critics argue that simple countermeasures could be designed to thwart the NMD system. While Russia has agreed to allow the development of NMD, some experts suggest that the system might compel China to increase its nuclear arsenal, which in turn could cause India and Pakistan to increase theirs as well.
Ballistic Missiles; National Missile Defense; Reagan, Ronald, and National Policy; Space-Based Weapons
A Cold War defense program initiated in the early 1980s by President Ronald Reagan, the Strategic Defense Initiative (SDI)—popularly referred to as
During the administration of President Ronald Reagan, a research and development program, initiated to build a space-based antiballistic missile...
Announced by President Reagan in March 1983 and called Star Wars by the press, it was designed to provide an effective antiballistic...