Sixty seconds after inviting a captive audience at a medical supply firm in Pennsylvania to laugh at Joe Biden on Thursday for having once referred to the 2009 H1N1 flu as “N1H1,” Donald Trump said that the 1918 flu pandemic happened in 1917. Ten seconds later, he made the same mistake again, which was at least the 40th time he has done so in the past two months, according to White House transcripts.

Trump’s strange inability to recall the most basic historical fact of the 1918 pandemic, which killed hundreds of thousands of Americans in its first year, including his own grandfather, gets weirder by the day. But the fact that the nearly 74-year-old president also frequently mangles, mispronounces or badly misreads words himself — and is willing to say things that make no sense to cover his stumbles — makes it bizarre for him to argue that Biden’s verbal slip-ups are proof that the former vice president is suffering cognitive decline.

That contradiction was on full display on Thursday, as Trump began his hit on Biden only after he appeared to stumble over his prepared text. Looking down at the podium as he read the remarks, Trump claimed that the Obama-Biden administration had depleted the national stockpile of masks during the response to the swine flu pandemic in 2009. “Most of the N95 masks were distributed during the… N1…” Trump read, twice pausing awkwardly as he came to the scientific name for the virus. He then looked up and apparently ad-libbed, “… H1 — now you know who says that, right?”

“‘N1H1,’ who says that?” Trump asked the audience at what was supposed to be an official presidential event related to the coronavirus crisis but he treated as a de facto campaign rally. Hearing no response from the dozens of workers gathered in the Allentown warehouse, he answered his own question: “Sleepy Joe Biden.”

“Remember?” Trump asked the workers, as though referring to a moment they would all be familiar with. “He said ‘the N1H1.’ I said, ‘Isn’t it the other way around?’ They said, ‘Yes, sir, but he said it, so it doesn’t make any difference.'”

The president then looked back down at his prepared text and continued reading from the point where he had begun to trip over the name of the virus before catching himself, and pivoting to attack Biden. “But during the H1N1,” Trump resumed, “and that’s the swine flu — and it was a pandemic in ’09 that was not well handled, at all. Got very poor marks.”

After claiming that the lack of personal protective equipment in the federal government’s national stockpile this year was entirely the fault of the Obama-Biden administration, even though he has been in charge of it for the past three years, Trump boasted that he was now replenishing supplies for the next outbreak. It was at this point that he once again misstated the date of the flu pandemic that killed his grandfather.

“Who would have thought? 1917. It could have been up to 100 million people were killed in — that was the Spanish flu — 1917,” the president told the workers who distribute personal protective equipment to hospitals. “Who would have thought this was going to happen? That’s over 100 years ago.”

While Biden did mistakenly refer to the swine flu virus as “N1H1″ during a debate in March, the order of the two halves of the term used to describe the virus — referring to subtypes of two proteins on its surface: hemagglutinin (H) and neuraminidase (N) — is unimportant. To understand why Trump thought this minor flub was better-known than it is, it helps to know that it has been mentioned five times by Sean Hannity on his Fox News show in the past two months, most recently on Monday, and featured repeatedly in the host’s tweets and online columns. Trump, who is an ardent viewer of that show, even repeated it back to Hannity during an interview with him in late March.

Four days before Biden mangled the name of the virus at his March 15 debate against Sen. Bernie Sanders, exactly the same mistake was made by Rep. Michael Cloud, a Republican Congressman from Texas who is an ardent Trump supporter, as he questioned Dr. Anthony Fauci at a televised hearing on the government’s response to the coronavirus threat. Cloud’s flub has not been mentioned by either Trump or Hannity.

The event in Pennsylvania’s Lehigh Valley on Thursday was Trump’s second official visit to a business involved in the effort to ramp up production of personal protective equipment in the past two weeks, and like the previous tour of a mask factory in Arizona, was also in a swing state the president is afraid of losing to Biden in November.

Both visits incorporated elements of the president’s rallies, including songs from the set list used at his campaign events to hype up the crowd — although in this case, the White House did not repeat the unforced error of blasting “Live and Let Die” as it had in Arizona when the president inspected the premises and urged Americans to get back to work despite the mortal threat still posed by the virus.

Both events were also overtly political in other ways. For instance, while Trump did not attack Biden in Arizona last week, he invited only the state’s Republican officials to attend the event at Honeywell’s retooled factory making N95 masks outside the airport in Phoenix and shunned Democrats.

In his remarks there, Trump praised Arizona’s Republican senator, Martha McSally, as “somebody that is bringing tremendous amounts of dollars back to her state that she loves so much,” essentially urging voters to back her in November. He made no mention of Arizona’s Democratic senator, Kyrsten Sinema. Similarly, Trump praised Arizona’s Republican governor, Doug Ducey, but failed to give any credit to the Democratic mayor of Phoenix, Kate Gallego, whose city owns the land the factory is on and had helped to get it up and running.

In Pennsylvania on Thursday, Trump began his remarks by exulting over the thousands of his supporters who had lined the road from the airport to the firm, packed closely together, ignoring the state’s stay-at-home order and social-distancing guidelines. He also encouraged defiance of the state’s Democratic governor, Tom Wolf. “We have to get your governor of Pennsylvania to start opening up a little bit,” Trump said. “You have areas of Pennsylvania that are barely affected, and they have — they want to keep them closed. Can’t do that,” he told the workers.

Further blurring the lines during what was billed as an official event, Trump also endorsed a Republican candidate for Congress, Sean Parnell, who is running against the Democratic incumbent, Rep. Conor Lamb, in a neighboring Pennsylvania district.

In both states, Trump also invited guests on stage, and on both occasions that included supporters who praised him. “It’s an honor to share the stage with you, it really is,” Carol Timm, a safety and training coordinator at the plant in Allentown told Trump on Thursday. “I think everybody knows I’ve been so excited about your visit.”

In Arizona the week before, he had invited two non-employees, Betty and Jorge Rivas, the owners of a Mexican restaurant who became Fox News stars after getting criticism for attending his rallies, to “say a few words.” Those words turned out to be fulsome praise for the president, who had previously tweeted his support for them. “I think you’re doing a great job,” Jorge Rivas told him, in remarks that were quickly shared online by an official Trump campaign account.

“I think we represent a lot of the Latino community that is very proud of the job that you’re doing, and I think most of us, all of us, all the Latinos are going to vote for you,” he added.

Betty Rivas, who was wearing a handmade jacket with Trump’s name and the acronym for his campaign slogan “Keep America Great” on the back, then added, “Latinos love Trump!”

Ever since Trump dealt a fatal blow to the daily coronavirus task force briefings by musing that perhaps his top scientists should investigate the possibility of injecting disinfectants into Covid-19 patients, the president’s communications staff, led by his campaign spokesperson turned press secretary, Kayleigh McEnany, has been looking for ways to let him campaign while appearing to be doing his job. That blurring of the line could have campaign finance implications, since presidents are required by law to reimburse the government from their campaign funds for any travel that is primarily about getting themselves re-elected, but it remains to be seen if Trump is paying for any of his recent tour of the swing states.

In late 2011, after Trump had flirted with and then thought better of running against President Barack Obama, he sat on the sidelines and heckled Obama for supposedly campaigning too much while in office. “All he wants to do is campaign, that’s frankly all he’s good at, and we’re paying for it,” Trump complained in a 2011 YouTube video that was deleted after his own election in 2016. “Our country is blowing up around us. There’s unrest all over the place. It’s being incompetently run, and this guy campaigns and we pay for it,” Trump said of Obama.

“Why doesn’t he pay for the planes and Air Force One and everything else that takes him to these destinations where he campaigns?” Trump asked then. “This is crazy. What he gets away with is unbelievable. He’s laughing at the American public for being stupid.”