David Litt writes: Donald Trump almost never laughs. The leader of the free world frequently displays a tight-lipped smile, but mirth-wise, that is as far as he will go. Except for the fact that Nazis don’t seem to mind him too much, Mr. Trump is the Captain von Trapp of commanders in chief.

It would be easy to dismiss this as a personality quirk. Some people are just hard laughs. Perhaps Mr. Trump is simply the hardest laugh of all. But the president’s laughter, or lack thereof, is a window into the way he views the world’s most difficult job. For the first time in recent memory, we have a commander in chief without a sense of humor — and America is paying the price.

For most presidents, humor is a tool for building bridges, especially with voters who may not be persuaded by their policy goals. When I wrote speeches for President Barack Obama, we would often open with a throwaway line, something about sports, the weather or the best barbecue joint in town. These were not exactly comedy gold. Still, they served a purpose. Even audience members who didn’t vote for Mr. Obama could appreciate one of his harmless asides.

The presidential equivalent of dad jokes — safe, well-placed quips that crowds are well primed to laugh at — are a bipartisan Oval Office tradition. Presidents George W. Bush, Bill Clinton and especially Ronald Reagan knew how to use laugh lines to win over skeptics. On his way into the operating room after a 1981 assassination attempt, Mr. Reagan famously declared to his doctors, “Please tell me you’re all Republicans.” The head surgeon, a Democrat, replied, “We’re all Republicans today.” Even at that moment, the president deftly cleared a patch of common ground.

Mr. Trump, to put it mildly, lacks this ability. With no talent for gracious one-liners, he finds himself ill at ease in front of all but the most adoring audiences. This is not to say that he is without charisma. The difference lies in the way his charisma is deployed. Surrounded by followers at rallies, he uses his well-honed sense of timing as a cudgel. He jeers. He mocks. His goal is to insult, rather than to entertain.

It should come as no surprise, then, that Mr. Trump governs the way he delivers a punch line: consolidating support among the hard core while alienating everybody else. [Continue reading…]