Difference between revisions of "Strategic Defense Initiative"

Revision as of 16:04, April 29, 2008

The Strategic Defense Initiative (SDI), which is also commonly called Star Wars (at first by detractors), was a proposal by U.S. President Ronald Reagan in 1983 to build a ground based and space based system to protect the U.S. from nuclear ballistic missiles. The system was never fully set up, but the research from this paved the way for the anti-ballistic missile systems of today, including the Patriot missile that provided the defense against Iraq missiles launched against American forces and Israel during the Gulf War. It is believed by some experts that the Soviet's response necessitated by SDI helped drive their financial and political downfall.

Goals of SDI

The basic goal of SDI was to intercept and destroy incoming nuclear ballistic missiles to prevent detonation over the U.S. In some scenarios, not all warheads would be intercepted, but enough would be to render mutually assured destruction moot. In the scenario of "partial protection", the U.S. would be immune from complete destruction, which would deter the USSR from launching a first strike. See Game Theory and Mutually Assured Destruction.

Components of SDI

There are a limited number of ways to prevent a ballistic missile from detonating over one's territory. A brief primer on nuclear attack will help explain the problems to be solved.

The Problems

Missiles with nuclear payloads are launched in two primary ways: as ground based intercontinental ballistic missiles, and as shorter range missiles, such as submarine-launched ballistic missiles (SLBMs) and submarine-launched cruise missiles (SLCMs).

• ICBMs are launched from the ground, travel into space, and return with the assistance of gravity. Most contain "multiple independently targeted reentry vehicles" or MIRVs. This means that a single ICBM can cause many nuclear warheads to detonate over multiple targets. Problems involved include detecting the launch, and deciding on what level to intercept the target. If the target is disabled before deployment of MIRVs, this obviously solves many problems. Once MIRVs are deployed, many more targets must be eliminated. Destroying an ICBM before it enters space is essentially impossible. Interception in space requires a pre-placed infrastructure. Interception after MIRV deployment involves ground-based systems.
• SLBMs and SLCMs present serious difficulties. SLBMs have a shorter time available to intercept, as they can be launched nearer to target. SLCMs are basically a first-strike weapon, travel short distances quickly and close to the ground.

The Solutions

Ground-based systems

Extended Range Interceptor (ERINT)

Ground-based systems must be able to detect a rapidly-approaching ballistic object, and destroy or divert that object well enough to avoid catastrophic damage to the target.

Space-based systems

Space-based systems generally aim to destroy a ballistic missile at the height of its trajectory. At this point, the missile is fragile and vulnerable. The difficulty lies in detecting the object, deploying the countermeasure, and successful interception. Several solutions have been proposed, including "Brilliant Pebbles", which would be non-ballistic kinetic missiles deployed to intercept the missile, and at low energy, deflect or destroy the ICBM.^[1]

Criticisms

Critiques of the original program focused on two central claims: that it was technologically impossible, and that even if it were possible, it would destabilize the conditions of MAD. Another such criticism is that, during the September 11 attack, the SDI would not have offered protection against this form of warfare and that rouge nations to not have the capability to launch a sophisticated nuclear attack against the United States.

1. ↑ "Brilliant Pebbles": The Revolutionary Idea for Strategic Defense, Heritage Foundation, 1990