Blackwater USA guards shot at Iraqi civilians as they tried to drive away from a Baghdad square on Sept. 16, according to a report compiled by the first U.S. soldiers to arrive at the scene, where they found no evidence that Iraqis had fired weapons. "It appeared to me they were fleeing the scene when they were engaged. It had every indication of an excessive shooting," said Lt. Col. Mike Tarsa, whose soldiers reached Nisoor Square 20 to 25 minutes after the gunfire subsided. His soldiers' report -- based upon their observations at the scene, eyewitness interviews and discussions with...