With his head bowed during a moment of silence outside the White House, President Barack Obama set the tone Friday for a nation marking a dark day with solemn ceremonies. Fourteen years ago Friday, terrorists hijacked four passenger planes and smashed two into New York's World Trade Center. A third jetliner rammed into the Pentagon outside Washington while a fourth one crash-landed on an empty field in Pennsylvania. More.
9/11 anniversary: America remembers lives lost on one of its darkest days