Lasers, popular myths, and Reuters

Reuters reports on progress on the US Air Force's airborne laser and includes the following bit of popular disinformation:

Philip Coyle, the Pentagon's chief weapons tester under former President Bill Clinton and now at the private Center for Defense Information, said in an e-mail reply to Reuters that its real effectiveness appeared doubtful.

"If a laser can be developed with enough power to penetrate the atmosphere and still be lethal once it reaches a target, an enemy would only need to put a reflective coating on the outside of its missiles to bounce off the laser beam, making it harmless," he said.

Now, remember that we are talking about a laser power enough to burn through a rocket's casing. A mirror exposed to that would not be a mirror for very long. Even the best mirrors under laboratory conditions are not 100% reflective. Further reflective coatings are, by their nature, fragile. Consequently, damage thresholds for laser mirrors even in a laboratory are much lower than damage thresholds for just the rocket. Worse, a mirror on the outside of a missile travelling through the atmosphere at high speed would soon look more like the chrome on an old car than like a mirror. In other words, any laser powerful enough to destroy a missile will easily destroy any reflective coating.

If Reuters had wanted to write an honest and accurate story, they could have found all this out by asking an informed person at the Pentagon to comment on Mr. Coyle's claim. They didn't.