Biden trips and falls at Air Force graduation ceremony.

President Joe Biden fell on stage at the U.S. Air Force Academy graduation after tripping over a sandbag, but the White House said he was "fine." Biden, who is 80 years old, has faced questions about his age and fitness to serve, but his personal doctor has said he is healthy and fit for the presidency. Biden's stumble is not the first by a national political figure, with past incidents involving President Gerald Ford, GOP Sen. Bob Dole, President Barack Obama, and former President Donald Trump.