A historian who has studied presidential oratory says Donald Trump’s campaign rallies offer unmistakable evidence of decline, arguing in a new op-ed that the president’s recent speeches rank among the worst ever delivered by a sitting U.S. president.

Ted Widmer, a former White House speechwriter and editor of the Library of America’s anthology American Speeches, wrote in The Guardian on Tuesday that Trump’s rallies, at their worst, offer evidence of “a president whose faculties are failing him.”

Over the past two months, Widmer argued, Americans have sat through the worst speeches ever delivered by a sitting president. Presidents have produced plenty of duds, he noted, but Trump’s belong in a category of their own: “they are routinely overflowing with vitriol against perceived enemies, groundless predictions of victory and delusions of grandeur.”

Many of the speeches barely hold together, Widmer wrote, and the president often loses his way during extended rants. He cited a rally in North Carolina at which Trump told the same story about Michael Dukakis and Willie Horton twice — a story dating to the 1988 presidential race, when Horton’s furlough from a Massachusetts prison became a defining line of attack against Dukakis, the Democratic nominee.

Widmer said the evidence also lies in Trump’s threats to rename oceans, his bragging about oil profits while Americans suffer, and his issuing of pardons to polluters who are violating the Clean Air Act, the landmark federal law that sets the nation’s air-pollution standards.

The 80-year-old president has increased his use of profanity, Widmer noted, pointing to examples such as Trump declaring that “Norway sucks,” calling Robert De Niro “a moron,” and using juvenile nicknames for his rivals. Trump has also boasted about acing his cognitive tests, insisting, “I’m a freaking genius.”

Widmer flagged a telling break from tradition as well. Past administrations routinely posted every presidential speech on the White House website, giving historians and the public a complete record of the president’s remarks, but Trump’s team will not post his rally speeches — a decision Widmer suggested reflects an awareness that they drag down the dignity of the office.

To illustrate how far the bar has dropped, Widmer reached back through the history of bad presidential speeches. William Henry Harrison’s marathon 1841 inaugural address, the longest in American history; James Buchanan’s embrace of the Dred Scott decision, the Supreme Court’s 1857 ruling that Black Americans were not U.S. citizens; and even Barry Goldwater’s fiery 1964 convention speech look restrained by comparison to Trump, he argued.

He also compared Trump to Richard Nixon, citing their “well-known problems with the truth” and shared hatred of enemies, while drawing a distinction on the campaign trail: Nixon’s 1970 campaign stops, made in a midterm election year of his own, featured dry talk of budgets and tax relief rather than critical language.

The White House has rejected claims that Trump has slipped, and his physician has pointed to a perfect score on a cognitive screening test.

Widmer conceded that Trump’s two-hour speeches take energy, and that the rallies still entertain the MAGA faithful, though their numbers are dwindling. But he questioned whether any of it serves the country — or even the Republican Party. The Trump brand may now be so toxic, he suggested, that sharing a stage with him does candidates more harm than good — a suggestion the election results will begin to test.

As voters head to the polls in Tuesday’s midterm elections, Widmer wrote that early signs point to a more balanced Washington, which he called a beginning.