MANCHESTER, Conn. — Omar Thornton sat calmly in a meeting with union representative and his supervisors as they showed a video of him stealing beer from the distributor where he worked. Busted, he didn't put up a fight, company officials said. He quietly signed a letter of resignation and was headed for the door when he pulled out a gun and started firing — "cold as ice," as one survivor described it. In the end, Thornton killed eight people and wounded two, then turned the gun on himself in a rampage Tuesday at Hartford Distributors where at least some of...