fter Somali militiamen killed eighteen U.S. soldiers in October 1993, President Clinton convened his national-security team. He sat silently while being briefed. Then, his aide Richard Clarke recalled, “When they had talked themselves out, Clinton stopped doodling and looked up. ‘Okay, here’s what we’re going to do.’”

We imagine White House meetings to be efficient and focused on grave matters; we don’t imagine the president dithering, daydreaming, or making idle scribbles—especially during moments of national crisis. But presidents, like the rest of us, doodle. Dwight Eisenhower drew sturdy, 1950s images: tables, pencils, nuclear weapons. A Herbert Hoover scrawl provided the pattern for a line of rompers. Ronald Reagan dispensed cheery cartoons to aides. John F. Kennedy reportedly doodled the word poverty at the last cabinet meeting before his death.

In an age of politics as scripted spectacle, these doodles, made without speechwriters or focus groups, promise a glimpse of the unguarded president. Because their meaning may be opaque even to the doodler himself, they invite us to interpret them—as befits our democracy—as we wish.

A skilled draftsman and architect, Jefferson was also a noted epicure. While in Europe in the 1780s, he became enamored of pasta—so much so that he stuck a feather in his inkwell, sketched out a design, and called it a “maccaroni”-making machine. In 1802, he served macaroni and cheese in the White House. ...