[Jack Simth]

Originally posted by oleg:
Excluding techical points, my major resentment to the development of new weapons is the question of containment. Would you really feel better if US develop a new laser antiaircraft weapon and few years later we will find a terrorist sitting outsite JFK with it ?

Commercial airplanes are already subject to essentially any anti-aircraft weapon out there; a terrorist with a new breed of one wouldn't be significantly more dangerous than a terrorist with an old breed of one. About the only difference between a laser-based Anti-Aircraft gun and a regular AA missle base (that's the size that is likely to happen in the next 5-10 years) in the hands of terrorists would be the method used to track them down once they started shooting. With either method, they could get a few planes; after that, a very large area would be a no-fly zone, preventing further kills. We'd then track down those immediately responsible (or try, at least), and then the US would then have the task of tracking down those who sponsered the attack (such hardware would not be cheap; any terrorist getting one is almost certain to have a sponser, government or otherwise). Fear of reprisals for the sponsors is likely the most realistic, readily implementable method of preventing such occurances.

All in all, not as bad of an event as, say, a nuke snuck through the borders and detonated; a possibility which has been around for decades. Sure, a nuke detonated near the ground is less effective than a nuke detonated higher up, but it would still be much more devastating than a few airplanes going down due to an AA attack.

The possibility of evil people getting their hands on something and using it towards evil ends isn't, in and of itself, a sufficient reason not to make it; if it seriously was, you'd want to elmininate auto manufactoring (a car makes a nasty weapon, especially after loading the back with exposives - anyone remember the Oklahoma City Bombing?), canning plants (the product can be poisoned; if done at the cannery with spot-checking terminated to do the terror thing, there is no way to tell until people turn up sick or dead), many fertilizers (bomb materials), computer information systems (viruses, spyware, identity theft, consumer information tracking, et cetera), kitchen knives (can be used to cut people), the mail system (historically has been used to deliver bombs and junk mail to people), et infinium. Most objects can be used by evil people in evil ways. If you worry about it too much, you'll be too frightened to get out of bed in the morning (also too frightened to stay in bed - a pillow can be used to suffocate someone).
Note: All listed uses of stuff above are evil, and shouldn't be done. Well, okay, the jury isn't necessarily out on junk mail yet.

If lasers can be turned into an effective anti-missle defense, then they have a useful purpose, and are worth a look at. Just think: What happens if ICBM's with nuclear warheads become effectively nullified by laser-based anti-missle systems? No nuclear war -> no devastating nuclear-induced world-ending climate change.