One of the strangest, and most useful, bombs employed in Iraq has been the concrete filled smart bomb (laser guided or JDAM). Why deliver a 500 pound bomb filled with concrete instead of explosives? You do that if you want to do some damage, but not a lot. Concrete JDAMs were first used in the 1990s to destroy anti-aircraft guns, radars and missiles that Saddam Hussein placed in residential areas. He believed that the Americans would not attack these weapons, for fear of hurting nearby civilians. But it turned out that a laser, or satellite (JDAM) guided concrete smart bomb...