Twenty-five years ago, we suffered the most devastating attack on U.S. soil since Pearl Harbor. Ratcheting up the shock from the death and destruction at the heart of Manhattan was uncertainty about the future: When might the terrorists strike again? Three days after the attack, President George W. Bush visited Ground Zero and delivered, impromptu, some of the most stirring words any president has spoken. Climbing atop a pile of rubble with a megaphone in hand, he was interrupted by voices in the crowd, complaining that they could not hear him. “I can hear you!” Bush responded.