Making Sense of Ballistic Missile Defense: An Assessment of Concepts and Systems for U.S. Boost-Phase Missile Defense in Comparison to Other Alternatives.

摘要

Current U.S. policy is to deploy as soon as technologically possible an effective National Missile Defense system capable of defending the territory of the United States against limited ballistic attack, whether accidental, unauthorized, or deliberate. The Missile Defense Agency (MDA) of the U.S. Department of Defense (DOD) plays a central role in supporting the Secretary of Defense (SECDEF) in developing and fielding an integrated, layered ballistic missile defense system. Ballistic missile defense (BMD) considers engaging threats during the boost phase, the midcourse phase, and the terminal phase of flight. Boost-phase defense encompasses engagements during the time period when the threat booster is still accelerating. The midcourse defense layer can be divided into (1) ascent phase, when the threat system is engaged prior to apogee, and (2) descent phase, when intercept occurs after apogee. The term early intercept is sometimes used to describe intercept after boost in the initial portions of the ascent phase of the threat system before apogee. Finally, terminal defense refers to engagements as and after warheads reenter the atmosphere and become subject to drag and reentry heating.