Pope Francis arrives in the U.S.

Pope Francis arrived from Cuba to start a six-day, three-city tour of America, his first official visit to a nation bitterly divided on global warming, income inequality and other contentious issues that the pontiff is expected to champion.

President Obama and his family, as well as Vice President Joe Biden, welcomed Francis on the runway at Joint Base Andrews, just outside the nation's capital, a heady departure from normal White House protocol that reflects the global celebrity and unusual appeal of the first Latin American pope.

Pope Francis visits the U.S. Officials are bracing for record-sized crowds, traffic nightmares and bustling vendors when the 78-year-old pontiff rides in his open…