On May 26, 1972 the United States and Soviet Union signed the Anti-Ballistic Missile (ABM) Treaty to bar either country from building nationwide ballistic missile defenses. President George W. Bush withdrew from the ABM Treaty on June 13, 2002 to counter a feared long-range ballistic missile threat from North Korea, and moved to deploy the U.S. Ground-Based Midcourse Defense (GMD) system at Fort Greely, Alaska and Vandenberg Air Force Base in California.
North Korea had a successful launch of a long-range missile last month and Iran reported testing a mid-range surface-to-air missile last week. U.S. missile defense must be prepared to address these potential threats, according to Air Force Brigadier General Kenneth E. Todorov.
The GMD system is the first and only operationally deployed missile defense program to defend the U.S. from a long-range ballistic missile attack. To do so it uses communication systems, fire control capabilities, and ground-based interceptors that detect, track, and destroy the target in mid-course flight utilizing multiple sensors. After the target is destroyed, it provides a post-attack kill assessment with the Sea Based X-Band Radar (SBX). Some suggestions for improvements of the overall system include a two-stage missile booster, heavier interceptor, and more capable sensors, including X-band AN/TPY-2 radars.
The classic problem of missile defense which no one has been able to fully solve after decades of trying, is the discrimination problem — telling the difference between actual warheads and decoys. Decoys can be unintentional, such as debris from the booster rocket traveling with the warhead through space, or intentional to frustrate defenses. In the future, some experts believe that intentional decoys will be used more widely.
Congress passed legislation in May 2012 to deploy missile interceptors to the East Coast of the U.S. by late 2015. In fact, Congress increased spending by $460 million on the U.S. GMD system of which $100 million is specifically allocated for the study of developing the East Coast site.
According to some experts, the East Coast site will also fulfill the purpose of the fourth stage of President Obama’s Phased Adaptive Approach (PAA) which includes Standard Missile-3 IIB interceptors in Poland and Romania. Some have criticized these positions as too far from locations, such as Iran, to fly fast enough to reach missiles launched from high trajectories. Replacing phase four of the PAA with the East Coast site is a possible mechanism to boost domestic missile defenses while also relieving Moscow’s concern that nearby defenses might undermine its own deterrent.
Emerging threats and technologies have motivated the U.S. to take action to boost its domestic missile defenses. The new East Coast site that is to be developed by 2015 represents an opportunity to improve the GMD system on the West Coast and deploy a more effective missile defense system on the East Coast.