In an interview published in the New York Times over the weekend, House Speaker Nancy Pelosi (D-Calif.) accused President Trump of something remarkable: She feared he would not be willing to give up power peacefully in 2020 if the election were close.

Of all the things Democrats have to worry about with Trump, this seemed a bit far-fetched to top her list. Sure, Trump called the 2016 election “rigged” (before he won, that is), but at the end of the day, peaceful transition of power is what defines American democracy. The president of the United States wouldn’t forsake that. Would he?

Like clockwork, Trump showed the world the very next day why Pelosi had reason to be privately worried about this for years.

Trump tweeted Sunday that his first two years were “stolen” (actually, he originally said they were “stollen” before he fixed his tweet) by special counsel Robert S. Mueller III’s investigation. And he reposted an inaccuracy-filled message from one of his supporters, conservative leader Jerry Falwell Jr., saying two years should be added to Trump’s term because Trump and his orbit had been investigated by the special counsel for his first two. “Reparations” is what Falwell called it, an idea Trump appeared to endorse by sharing it with his 60 million Twitter followers and then expounding on why he felt he deserved more time in office than the Constitution allows.

I guess we need to say this: Giving a president extra time to be president because there was a legitimate investigation related to his conduct is a remarkably undemocratic idea. It’s not like Trump’s ability to be president stopped because of Mueller’s investigation. He signed into law a tax bill. He played a role in shutting down the government, twice. He installed two Supreme Court justices and a record number of federal court judges.

And even if the idea of extending his term is just that to Trump — an idea he doesn’t expect to go anywhere, him spouting off steam about the Mueller investigation — the president of the United States is using language that he could use to lay a framework to call into question the 2020 election’s legitimacy, if he wanted to.

Trump has already arguably contributed to an erosion of Americans’ faith in the democratic process by repeatedly making unsubstantiated claims about massive voter fraud and refusing to acknowledge in a real way Russian interference in the 2016 election that attempted to sway voters in his favor.

And that seems to be what Pelosi is most worried about with Trump. If an election doesn’t go his way, she worries he’ll seize any opportunity to convince his loyal supporters that it was rigged and launch the nation into some kind of constitutional crisis that somehow protects his power. Here’s what Pelosi told the New York Times’s Glenn Thrush when they chatted Wednesday — days before Trump’s “stollen” tweets:

She shared her then-private concerns in 2018 that Trump would contest the House of Representatives elections: “If we win by four seats, by a thousand votes each, he’s not going to respect the election."

If the battle for the House majority was close, she said she worried: “He would poison the public mind. He would challenge each of the races; he would say you can’t seat these people. We had to win. Imagine if we hadn’t won — oh, don’t even imagine. So, as we go forward, we have to have the same approach.”

She added that she thinks Democrats “have to be prepared” Trump would do the same in 2020 if the election is even remotely close.

That, in a nutshell, is why Pelosi does not support impeachment of Trump in the wake of the Mueller report suggesting he broke the law. It would risk weakening Democrats’ strength in the 2020 election, then risk a constitutional crisis if they don’t win outright.

It’s not a coincidence that Pelosi is sharing her private concerns about Trump’s respect for the bedrock of American democracy now. Polls show that while the majority of Americans think Trump lied, they don’t support impeaching him. But even so, some lawmakers (and presidential candidates) are calling for impeaching Trump after the Mueller report outlined evidence that he tried to block, control or end the independent investigation into Russian election interference.

Pelosi is arguing that impeachment could lead to a constitutional crisis of a different kind. It’s one more tool she has to convince the pro-impeachers to stand down. And Trump just helped her prove her point.