Not long after that tweet, news emerged that the FBI had arrested a suspect in the bombing attacks. (It is unclear whether Trump had been informed of the arrest of the suspect, Cesar Sayoc, at the time he was throwing around this unsubstantiated and inflammatory claim.) Trump, at a preplanned appearance, returned to his somber tone.

“These terrorizing acts are despicable and have no place in our country,” he said. “We must never allow political violence to take root in America. Cannot let it happen. And I’m committed to doing everything in my power as president to stop it.”

A few minutes later, he was making “Lock him up” jokes.

Part of the problem is that, as I have written, Trump still does not grasp the weight that his statements carry now that he is president. When he was a private businessman, a TV personality, and a Howard Stern guest, he could spitball, hypothesize, or simply BS without serious repercussions. When the president of the United States makes comments, however, warships turn, markets reverse, allies reassess, and, as The Washington Post reported this week, legions of government workers scramble to make bogus assertions reality. Trump clearly enjoys the power of the presidency, but he remains insensitive to its responsibility. The dangers are on display every time Trump embraces a conspiracy theory, as he does regularly. His false-flag innuendo was as inevitable as it was irresponsible.

But there is a more elaborate confusion at play. Every American president has to wrestle with the dual burden of being the leader of the nation as well as the leader of his political party. Inevitably, there are places where he errs. Every president is criticized for using Air Force One and official time to campaign for candidates of his own party. Eight years ago, it was a multiday scandal when Barack Obama carelessly referred to political “enemies”; now that’s just Tuesday morning. Trump has repeatedly stunned Washington by injecting naked politics into occasions and tasks that were once meant to be beyond the grubby reach of partisanship.

Max Abrahms: Stop trying to guess the mail bomber’s motivation.

An attempted multiperson assassination seems like an obvious place to err on the side of avoiding partisanship. But there is a make-or-break election approaching for Trump, and he could not resist the impulse to turn the bomb threats into an advantage for the Republican Party.

In a one-party state, there’s no such problem of separation. The leader of the party and the leader of the nation are one and the same—and the interest of the party and the interest of the nation are, at least in theory, also the same.

There’s plenty of evidence to suggest that Trump sometimes yearns for a one-party state. It’s a thread that runs through his opposition to critical press coverage and threats to throttle the media, his celebration of violence against the press, his incitements to violence against protesters, and his threats to prosecute and imprison political rivals like Hillary Clinton.