A Chicago police officer suffered a stab wound to the leg, Sunday, and three others were injured during a day of protests around the NATO summit. Chicago police Supt. Garry McCarthy did not know what was used to stab the officer and became emotional when discussing the crowd with which his officers dealt. "If you think it's easy to ask people to do what they did, it's not," he said, pausing to gain his composure. "Asking people to put themselves in harm's way, knowing that they're going to get assaulted, and to be able to stand there and take it,...