The leader of the free world is meant to behave with a high level of decorum. But that doesn't always pan out. The commanders in chief listed here all had lapses in judgment that betrayed their human side. Their too-human side, perhaps. If you're a US president, you should maybe think before you act.
Like this time George W. chest-bumped an Air Force Academy cadet at his graduation ceremony. Definitely not a common sight for the president.