The US Air Force wants to go after enemy troops equipped with shoulder-fired anti-aircraft missiles. In the past, it was assumed that such targets would be impossible to spot (at least not fast enough to attack them) and that such missiles could be avoided by simply flying higher and using flares. But new developments in infrared sensor technology and the existing technology for GPS coordinates may change this. In theory, sensors on an orbiting drone could detect the flash of a shoulder-fired missile launch and calculate the exact position of the shooter within a few feet. Then an assigned aircraft (getting the coordinates from an automated datalink) could lob a 500 pound guided bomb to those coordinates, with the bomb landing within a minute of missile launch, perhaps even faster (assuming there are no annoying JAG lawyers in the loop who must clear a target in an inhabited area before it can be attacked). While the obvious solution is for the gunners to adopt a "shoot and run" tactic, some of the world's shoulder-fired missiles are not fire and forget but ride a laser beam to the target. This technology is available now, but still has to be assembled and deployed. It can, besides shoulder-fired rockets (whatever their targets) also detect artillery and ballistic missiles. The next generation of infrared detectors (due in a couple of years) will be able to detect small arms fire. This would be handy for detecting snipers, or for guiding ground troops into a battle zone, or to tell a ground commander that more than one enemy unit is firing on him.--Stephen V Cole