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Issue: Missile Defense: Study Questions

Introduction to the Issue

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(1) What is the ABM Treaty and what effect does it have on nuclear strategy? (Answer)

(2) What are the advantages of attacking an Inter Continetal Ballistic Missile during its boost phase? What are the other three phases of ICBM flight? (Answer)

(3) What are the counter measures that might work against a Ballistic Missile Defense system? (Answer)

(4) Why do strategic (intermediate range) and tactical (short range) missiles require slightly different defense technologies? (Answer)

(5) What are the problems with the flight tests for NMD? (Answer)

(6)Why do many NMD experts prefer to begin with a sea-based system rather than a ground-based system? (Answer)

(7) How might the deployment of an NMD in the United States alter the existing efforts for arms control in the rest of the world? (Answer)



Answer to question #1:

The ABM Treaty was signed by the Soviet Union and the United States in 1972. It limitted the number of anti-ballistic missile deployment sites to two in each country in an attempt to slow down the arms race and to decrease the possibility of a nuclear war. People feared that a missile defense system would increase the likelihood of a first strike because a nation that posessed such a system could defend against a retaliatory attack.
(**For more see Strategy)

In December 1991 the Soviet Union ceased to be a political body. As a result, the ABM Treaty became the subject of much debate. Those who support National Missile Defense deployment in the United States feel that the treaty lost its significance when the Soviet Union collapsed in 1991. They argue that the importance of attaining a National Missile Defense overrides that of maintaining U.S. agreement with the former Soviet Union. Proponents in the U.S. who oppose National Missile Defense believe that the limitations on missile defense as outlined in the ABM Treaty are necessary in order to prevent a second arms race. Furthermore, if the U.S. were to violate the agreement, it may disrupt its relationship with Russia as well as upset the rest of the international community.

Answer to question #2:

Each flight phase of an Inter Continental Ballistic Missile (ICBM) requires a unique strategy for defense. The boost phase is that in which the missile is lifted from its launch site into the atmosphere to about 125 miles.

The boost phase lasts for 3-5 minutes and has two distinct advantages to a defense strategy:

  • The bright flame produced by the rocket boosters allows for the space-based radar systems to detect an oncoming missile with more ease.
  • The target of the boost-phase missile is large and easier to hit becasue one vehicle carries all of the warheads

The other 3 phases are the post-boost phase, the midcourse phase, and the terminal phase.

Answer to question #3:

A National Missile Defense system would have missile interceptors located in space. There is no air resistance or friction in space which means that an ICBM can release decoys during flight that travel at the same speed as the missile. It is possible for a typical missile to release as many as ten decoys for each warhead. This makes it nearly impossible for a defense system to detect the actual warheads. The attacker may also diguise the warheads by hiding them in metallic ballon decoys. One alternative counter measure to the decoy method would be to enclose the warhead inside of a metallic shroud which would be cooled with a bit of liquid nitrogen. This reduces the range at which an "infrared-homing kill vehicle" could detect the warhead

Answer to question #4:

The technology for defending against strategic and tactical weapons varies due to their different velocities and ranges.

The longer the flight of an oncoming missile, the more energy and velocity is required to launch that vehicle to its target. The long flight and high speeds of strategic weapons (ICBMs and SLBMs) require a swift interceptor that could meet the velocity of the strategic weapon that it targets. The shorter-range tactical weapons require less boost because they travel less distance. This means that the interceptor will have less time to destroy the tactical missile. These missiles need to be detected and brought down quickly in order to catch them in their short flight period.

Answer to question #5:

As of February 2000 two intercept tests have been conducted.

The first test which took place on October 2, 1999, hit the target. Yet the target was a single warhead with a pre-determined launch time and direction. There was also a homing device on the first test which helped it identify its target. Furthermore, the one large balloon decoy that the warhead released during flight also helped the kill vehicle identify its target.

The second test took place on January 19, 2000. This test did not succeed at hitting the target. Reports indicated that two of the infrared sensors failed six seconds before impact.

Both tests were no true indicators of the progress of NMD technologies because they were conducted under controlled conditions. More importantly, the various components of the NMD system, which include the interceptor, radar, and computer systems, have not been tested.

Answer to question #6:

Ships are very mobile and have the ability to reposition themselves as needed. They can move to meet threats against the U.S. as well as come to the rescue of its allies. The existing program for NMD places the main site in Alska. This allows for defense against countries such as Russia , North Korea, or China, yet limits our ability to defend against missiles that are travelling in directions towards the East Coast. The great size of the United States makes it very difficult to defend with only one or two sites. Sea-based defense systems would allow for multiple defense sites that could move to the areas that pose the greatest threat.

Answer to question #7:

If the United States goes ahead with their NMD program, it will most likely instigate other countries to retaliate by equipping all of their warheads with counter measures. These counter measures would allow for offensive missiles to "beat" any defensive system. Furthermore, the strain between the United States and China would worsen with the deployment of NMD and may instigate a Chinese nuclear build-up. If China begins to increase their nuclear arsenal, India and Pakistan will likely to follow. Russia will most likely respond with suspicion and will eventually invest in the technology for more advanced nuclear weapons. National Missile Defense undermines the concept of deterrence and has the potential to spark another arms race.