"The ATL is the smaller of Boeing's two airborne deathray projects: the larger, the jumbo-jet mounted Airborne Laser (ABL) is said to be in the megawatt range and is intended to destroy intercontinental missiles boosting up through the atmosphere, beaming them out of existence from hundreds of kilometres away.
The ATL has no such clearly-defined purpose, but it has been speculated that it could be used as a silent, invisible, traceless sniper. The carrying aircraft might be hidden by distance or darkness, and selected enemies of America - or cars, buildings, cell towers etc - would appear to suddenly and inexplicably burst into flame. Or at any rate suffer a nasty burn..." The Register Engadget
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