Tragedy, humiliation and loss are the building blocks of these giants, as the Burns story shows. A lifetime of comfort, more often than not, is no path to greatness.

Don’t expect Obama to be a Roosevelt. He doesn’t seem comfortable around strangers or fellow politicians. Bill Clinton, Ronald Reagan, John F. Kennedy, T.R. and F.D.R. were naturals. Obama can deliver a terrific speech and has a first-rate intellect. But making music from the messy notes of politics is not in his character. He’s never learned to use his personal narrative to advance his policies.

But he can learn something from the Roosevelts about the mechanics of politics. The bully pulpit (a term T.R. basically invented) has been in the closet, gathering dust, for most of Obama’s presidency. Teddy loved to call out his enemies. A political pugilist, he sometimes gave 20 speeches a day on behalf of his progressive agenda. When a man fired a shot at him in 1912, he continued to speak for nearly an hour, even with a bullet lodged between his ribs and his shirt bloodied. It was an occupational hazard of the trade, he remarked.

Beyond the outsize personality, T.R. advanced great notions — public land, a right to clean air, water and food, protections for workers, restraints on big business. As a Republican, Teddy was well ahead of his time, and faced strenuous opposition by a reactive coalition that is the modern equivalent of today’s Republican Party.

His Democratic cousin did the same thing with a minimum wage and Social Security (socialism!), and moved an isolationist nation along, gradually, to see that the Nazi war machine had to be stopped. He also never shied from a fight. “They are unanimous in their hate for me,” he said of his opponents in 1936, “and I welcome their hatred.”

Obama’s opponents hate him as well, with the added strain of racism, which makes it hard for him to confront them directly without stirring up things that have nothing to do with his policies.

No moment in politics is frozen. Just in the last few days, Obama has shown that he’s trying to find his way out of a rudderless summer. Thursday’s call with Prime Minister David Cameron of Britain to press NATO to confront the Islamic State psychopaths was a small echo of the old Roosevelt-Churchill two-step that helped save the world. ISIS is not Nazi Germany. But it must be crushed.