Pope's visit will produce largest security operation in U.S. history

Federal authorities are mobilizing one of the largest security operations in U.S. history ahead of Pope Francis’s arrival Tuesday, an effort that is straining law enforcement resources in Washington, New York and Philadelphia. The pope’s five-day tour, his first in the United States, will include appearances at the White House and Congress, a parade on Constitution Avenue in Washington, a Mass at Madison Square Garden, a procession through Central Park in New York, and an open air Mass with up to 1.5 million people in Philadelphia.