President Donald Trump is a righty, but before him a veritable flood of left-handed United States presidents held office. It's tough to track presidential handedness throughout history because until recently many naturally left-handed children were forced to write with their right hands.
In the past several decades alone, however, the Oval Office lefties have come out of the woodwork, including Barack Obama, Bill Clinton, George H.W. Bush, Gerald Ford and Herbert Hoover. Ronald Reagan was considered ambidextrous, probably because he was born lefty, but forced in childhood to write right-handed. Harry S. Truman and James Garfield also fell into the ambidextrous category. So, now that Trump has taken office, of the last 15 presidents, seven classify as either straight up lefty or ambidextrous, a ratio that is well above the average left-handed population [source: Marcin].
Why so many presidential lefties? It's tough to pinpoint entirely, but the lefty predisposition to excellence in complicated thought processes could be one reason.