The president included the stop in Italy after meetings with European leaders in Brussels on the crisis in Ukraine and other matters.
Before nightfall in Rome, Mr. Obama got a private tour of the Colosseum, the ancient Roman amphitheater where gladiators battled and Christians were executed. The president marveled that the structure is “bigger than some current baseball stadiums.”
As he walked with his tour guide, Mr. Obama asked her, “Let’s say someone is on the ground. He didn’t have to kill them, did he?”
Reporters couldn’t hear the guide’s answer.