Critics Say US Antimissile Defense Flawed, Dangerous

Hugh Pickens writes "The New York Times reports that President Obama's plans for reducing America's nuclear arsenal and defeating Iran's missiles rely heavily on a new generation of antimissile defenses which last year he called 'proven and effective.' Now a new analysis being published by two antimissile critics at MIT and Cornell casts doubt on the reliability of the SM-3 rocket-powered interceptor. The Pentagon asserts that the SM-3, or Standard Missile 3, had intercepted 84 percent of incoming targets in tests. But a re-examination of results from 10 of those apparently successful tests by Theodore A. Postol and George N. Lewis finds only one or two successful intercepts, for a success rate of 10 to 20 percent. Most of the approaching warheads, they say, would have been knocked off course but not destroyed, and while that might work against a conventionally armed missile, it suggests that a nuclear warhead might still detonate. 'The system is highly fragile and brittle and will intercept warheads only by accident, if ever,' says Dr. Postol, a former Pentagon science adviser who forcefully criticized the performance of the Patriot antimissile system in the 1991 Persian Gulf war. Dr. Postol says the SM-3 interceptor must shatter the warhead directly, and public statements of the Pentagon agency seem to suggest that it agrees. In combat, the scientists added, 'the warhead would have not been destroyed, but would have continued toward the target.'"

Comments

It's a whole lot more basic than that

[Ancient_Hacker]

The problems with anti-missile defense are more basic than that:

(1) Basic geometry -- you have to station a slew of defensive missiles every 20 miles along your borders. That's because you are not going to hit anything going Mach 12 across your path-- you need a close to head-on intercept angle.

(2) Cheap and easy countermeasures. Even if you bankrupt your country setting up (1), the bad guys just switch to using sub or boat launched cruise missiles. Or low-trajectory ICBM's. Or put the bomb on a freight or passenger plane. It's mighty foolish to spend a trillion $ and have all that effort counteracted by a visit to UPS and $187.54.

JR Oppenheimer did this math in his head in 1952 as he was testifying to a govt comittee. Nothing has changed since then.

 

Re:all it has to do is damage a warhead

[Anonymous Coward]

"a warhead is pretty fragile and a lot of things have to work in unison and perfectly together to produce a nuclear explosion. if you hit it hard enough to damage it and prevent an explosion it's good enough"

Not really, this missile is targeting re-entry vehicles that must survive the shock of launch, the heat of re-entry, and frequently contain ground penetrating warheads (for use against hard targets like other silos or bases).

Glancing blows will only deflect the impact point.

You have four main weapon delivery mechanisms:
1. High altitude burst, for EMP, but you risk taking out your own equipment. (Taking out your recon satellites in the opening shot of a war)
2. Low altitude burst, maximum destruction of soft targets
3. Ground burst / laydown (deprecated somewhat in favour of ground penetrating), some hard targets, and maximum area denial (fallout)
4. ground penetrating, maximum damage to well protected hard targets or wide area damage to structures in solid ground (shock waves through the ground destroying foundations for quite some distance)

These warheads are complex, but hardly fragile.

Re: all it has to do is damage a warhead

[Shakrai]

and 1/3 were from a SCUD missile that landed on a barracks after being deflected from its target by a Patriot missile.

Incorrect. The Dhahran barracks were not hit by a "deflected" missile. No intercept of that incoming Scud was ever attempted. There was a software bug in the Patriot Missile system that caused the system clock to drift. The longer the system was kept running without being restarted the worse the drift got. As a consequence of this the system never detected the incoming threat and no intercept was attempted.