Throughout his first term, President Donald Trump has set new standards for reckless and divisive conduct in office. His latest declaration marks a dangerous new low. Thursday morning he suggested (on Twitter, of course) that the election in November, which will rely more heavily than usual on mail-in voting due to the pandemic, was bound to be inaccurate and fraudulent, and floated the idea of delaying it.

When confronted with Trump’s outrageous behavior in the past, Republicans in Congress have generally pleaded ignorance or offered qualified defenses. They should recognize this latest intervention as something different — an indefensible provocation that could do lasting damage to American democracy.

Trump offered no evidence to support his claim that voting by mail is an invitation to fraud. One reason for this is that there isn’t any. Of the 250 million votes cast by mail nationally over the past 20 years, about 0.00006% were found to be fraudulent. Nor does voting by mail favor one party over the other in terms of vote share or turnout. What the evidence does show is that unsubstantiated claims of voter fraud significantly reduce confidence in electoral integrity, especially when they cohere with a given voter’s politics. That may be one reason why nearly 6 in 10 Americans now say that they don’t have faith in their own elections.

To be clear: Trump couldn’t delay the election even if he wanted to. Conceivably, Congress could do so by passing a law, but there’s no chance whatever House Democrats would agree. To their credit, Senate Majority Leader Mitch McConnell and House Minority Leader Kevin McCarthy both clearly stated, after Trump’s tweet, that Election Day won’t be changed.

It’s safe to assume, then, that Trump knows the vote won’t actually be delayed and has a different aim. He’s laying the groundwork to declare the result illegitimate. This would allow him to say that he didn’t really lose: He might be obliged to leave office, but only because the election was stolen.

Even those inclined to support the president likely understand that the main goal of this strategy is to gratify his insatiable vanity. Yet the cost to the country could still be crippling. It risks fomenting worsening civil disorder, further polarizing politics, and undermining the system’s already-diminished ability to yield stable and consensual government.

Ideally, this latest assault on democratic norms will lead Republicans to see that Trump is not their friend. Ideally, many more of them will follow McConnell’s lead and make plain that they’ll do nothing to legitimize this abhorrent tactic. As with so many aspects of this presidency, though, the damage may already have been done.

From an editorial on Bloomberg Opinion