President Trump is recovering after a bullet fired at his head grazed his ear during a Butler, Pennsylvania, rally. The gunman and one Trump supporter are dead. Coming days after I wrote in the Sun that President Biden urged donors to “put a bullseye on Trump,” we can hope that the apparent assassination attempt turns the election from ad hominem attacks back to policy.

“President Trump thanks law enforcement and first responders for their quick action during this heinous act,” Trump’s communications director, Steven Chung, said in a statement. “He is fine and is being checked out at a local medical facility.”

As Secret Service agents rushed a bloodied but unbowed Trump off the stage, he mouthed, “Fight!” and waved to the crowd. He pumped a fist thrust in the air with a defiant grimace. His refusal to cower, and indeed his attempt to make the most of the moment, echoed a similar dark day in October 1912.

Exiting a car, President Theodore Roosevelt — like Trump, seeking a return to the White House — was shot in the chest by a Manhattan barman, ‎John Schrank, who opposed his run. The Rough Rider coughed into his hand and didn’t see any frothing blood.

“He pinked me,” he said, and judged his heart and lungs had escaped a mortal wound.

Schrank, who had stalked Roosevelt for months across several states, waited until Wisconsin to strike because it lacked a death penalty statute. The gunman’s moment came at Milwaukee, which, by eerie coincidence, will host the Republican National Convention this week.

Roosevelt was spared death by the folded pages of a speech and a spectacle case in his pocket. Against the urging of doctors and aides, he went ahead with a speech titled, “Progressive Cause Greater Than Any Individual.” He spoke at the Gilpatrick Hotel, where the Hyatt Regency now stands.

“I have just been shot,” Roosevelt told the audience. “But it takes more than that to kill a bull moose.” The quip added to his legend and gave a mascot to his upstart Progressive Party. I’ve read the transcript of the speech, and the former president keeps brushing off attempts to get him to stop and seek medical attention.

When Roosevelt left the stage, everyone wanted to shake his hand. His patience wore thin, as he suspected each one was hoping for the honor of being the last to shake his hand before he died. The incumbent, President Taft, and the challenger, President Wilson, briefly suspended their campaigns. Similarly, President Biden is suspending his ads and paused campaigning out of his headquarters.

For the balance of that election year, candidates and their crowds were jittery. That may be the case this year. In Roosevelt’s case, he remained ready. Weeks later, when a camera flashbulb popped, a crowd fell into stunned silence.

“Ah,” the former president said, “shot again!” and laughed.

Trump looked like, given the chance, he would have followed Roosevelt’s example. A showman like his predecessor, he knew history was being made. For months, he has warned that the rhetoric of Mr. Biden and Democrats might result in an attempt on his life. He was ready as his worst fears seemed realized.

The Secret Service had to stuff Trump into a waiting car against his will, bending the arm with that outstretched fist. “Let me get my shoes,” he said, a moment that invoked Vice President Cheney on 9/11, who said agents hauled him to the White House bunker with such speed that his feet didn’t touch the carpet.

In 1981, when an assassin struck President Reagan, he recalled the words of the British prime minister, Winston Churchill, after coming under fire for the first time as a young man. “There’s no more exhilarating feeling,” he said, “than being shot at without result.”

There has been a result for Trump, as there was for Roosevelt and Trump. Reagan, nevertheless, had more quips ready. “Honey,” he told First Lady Nancy Reagan, “I forgot to duck.” As doctors prepared him for surgery he remarked, “I hope you’re all Republicans.”

“Today,” replied the surgeon, Joseph Giordano, a liberal Democrat, “we’re all Republicans.”

After the shooting, Mr. Biden called political violence “not appropriate.” The thing about democracy is that it hands up campaigns that are bigger than any individual, and the ballot is how we stop a donkey, an elephant, or a bull moose.