Ultimate umbrella

Star Wars: missile defense
Howzit work?
A tough task
When to hit that missile?

The launch of a Patriot missile - the same defensive missile which gained fame during the Gulf War.

Image Ballistic Missile Defense Organization.


Two if by sea
The United States has spent billions on various missile-defense schemes, and plenty of partly-finished projects are lying around in the pentagon's basement. According to Baker Spring of the Heritage Foundation, some of this overlooked technology could quickly be pressed into service.

Patriot missile launch
Instead of concentrating on a land-based national missile defense, as the pentagon is currently doing, Spring argues that upgrading the Naval Theater-Wide defense (NTW) is "a first step." A hyped-up NTW, based on ships, might be able to knock out missiles during the ascent phase, when the missiles are above the atmosphere, but before they have released their warheads.

A floating system got the Why Files thinking that it would only be useful against coastal launches. How far inland could such a ship-based system reach? Hard to say, Spring says. "It depends on the nature of the missile trajectory and downrange distance of the navy launcher. There's not a single answer. The main thing is not the range of the anti-missile missile, but the speed by which it can get to the assigned target area." And that speed, as we'll see shortly, is restricted by the 1972 Anti-Ballistic Missile treaty.

The Navy system is one of many systems ideas for intercepting various phases of a missile attack.

  • Ascent phase: while the enemy rocket is burning or before it releases warheads.
  • Mid-course phase: while the missile and warheads are above the atmosphere
  • Descent (terminal) phase: just prior to impact (the Patriot missile approach).
Each phase has its own requirements, and its advantages and disadvantages, as you'll see in our handy-dandy, simple-as-pie table of missile defense.

Missile defense -- the table

When interceptedAdvantagesDisadvantages
Ascent phaseEasy to see targets
Targets moving slowly
One shot kills many warheads and decoys
Weapons may fall back on enemy territory, dissuading opponents from launching.
Broadest protection
Ultra-fast response needed
Danger of mistaken launch
Must be based in space or (for coastal launches) on ships
Most experimental technology
Mid-courseMore time to reactDefense probably must be based in space, except for last part of mid-course defense
Decoys confuse defense
Descent phaseLongest response time
Based on land
Most familiar approach
Decoys have slowed down or burned up
Warheads moving fastest
Hard to distinguish missile fragments from warheads
Bomb fragments can hit your territory
Little or no chance for a second try
Still unproved

Currently, descent-phase research is most advanced in projects like an enhanced version of the Patriot missile and the Theater High-Altitude Area Defense. Because these systems would not protect the entire United States, achieving the national missile defense that interests Congress requires technology that attacks during the ascent or mid-course phases.

Three if by space
The goal of universal protection could return the discussion to Star Wars -- the space-based missile defense." Spring sees a revived NTW as only a first step, and proposes that the defense then move to space. An orbiting defense called "brilliant pebbles," Spring says, would strike enemy rockets during the boost phase from 1,000 satellites in low orbit. "It was never killed for technical reasons, but for political reasons," he maintains. " It's not dramatically more sophisticated than what [President George] Bush advocated. It's a question of rehabilitating the program and putting it back on track."

Although Lehner of the ballistic missile office says brilliant pebbles is "not in the cards," Spring says it would have a secondary benefit of deterring a rogue state from attacking. "If there's a boost-phase capability, there's a significant likelihood that chemical or biological weapons would rain down on his territory, and his calculations of deterrence might be different."

We'd bet our bottom Why File you could learn something from our missile-blasting bibliography.

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