The first official act of the Trump Administration was the Inauguration—and, within hours, a lie delivered from the White House press room about how this had been “the largest audience to ever witness an Inauguration, period, both in person and around the globe.” That episode seems so long ago, and many thousands of lies ago. But as the world now faces a pandemic, it has never been more essential to recall that norm-setting performance and to admit what has been demonstrated on a daily basis about the public official who carries ultimate responsibility for the public safety of American citizens: Donald Trump is incapable of truth, heedless of science, and hostage to the demands of his insatiable ego.

Recall, since the start of the coronavirus crisis, the litany of bogus assurances, “hunches,” misinformation, magical thinking, drive-by political shootings, and self-stroking:

“We have it under control. It’s going to be just fine.”

“By April, you know, in theory, when it gets a little warmer, it miraculously goes away.”

“The Obama Administration made a decision on testing that turned out to be detrimental to what we’re doing . . . ”

“We’re going very substantially down, not up. . . . We have it so well under control. I mean, we really have done a very good job.”

“As of right now and yesterday, anybody that needs a test [can have one], that’s the thing, and the tests are all perfect, like the letter was perfect—the transcription was perfect.”

“They would like to have the people come off [the Grand Princess cruise ship, off the coast of California]. I would like to have the people stay. . . . Because I like the numbers being where they are.”

Physicians and public-health officials told me, as they have told many other journalists, that they are dispirited by the President’s public pronouncements, saying that he has added to the danger of the crisis by minimizing its scale and the need for rigorous precautions. Has there ever been a less serious President?

Michael Mina, an epidemiologist at Harvard’s T. H. Chan School of Public Health and a physician at Brigham and Women’s Hospital, told me, “We need the President to put the well-being of the American people before his reëlection. And that requires open discussion and accurate information so that we can, along the way, condition people to what’s coming next, not to pretend that this is not a serious threat and they should just continue life as usual. His interest in being reëlected is in conflict with the truth and people’s best interests.”

Trump, Mina went on to say, “sees downplaying the threat as a way to look good. He can say all the words he wants, but that won’t change the biology of this virus, which will spread unabated unless we take the proper steps.”

Marc Lipsitch, a professor of epidemiology at Harvard’s School of Public Health, told me, “It is just false and unproductive to say that things are under control, and it is false to say that anyone should go to work with a ‘minor’ case of the virus. . . . One thing you can say is that federalism is our friend. There are top-notch people in state and local health departments. They are very capable and put out good information.”

Trump’s misstatements and understatements in recent weeks are consistent with his general attitude toward empiricism. Which is to say, he has never shown much regard for fact. In the past, Trump has said that climate change is a Chinese “hoax” and that “vaccines can be very dangerous.” Disinformation and misinformation are rampant in his mental universe. Trump recently gave the Presidential Medal of Freedom to Rush Limbaugh, who said, last month, “The coronavirus is the common cold, folks.” One of Trump’s ardent supporters in the Senate, Tom Cotton, of Arkansas, is among those who have suggested publicly that “we at least need to ask the question” of whether the virus was a bioweapon deliberately created in a Chinese laboratory outside the city of Wuhan—a theory rehashed in places like the Washington Times.

It would be colossally wrong and distracting to blame Donald Trump for too much. No President can single-handedly stave off something of this order, and the instinct to avoid general panic is not without reason. But Trump’s overweening self-confidence, his carelessness with language, and his suspicion of government professionals—another facet of his fear of “the deep state”—exacerbates public anxiety and contributes to the chaotic national response to this crisis. When he has taken the opportunity to speak, he has too often chosen the paths of obfuscation, misdirection, and falsehood. Only Trump would put Mike Pence in charge of the coronavirus crisis when, as the governor of Indiana, Pence initially bungled the public-health response to an outbreak of H.I.V. in his state.

Time and again during this crisis, Trump has questioned the science put in front of him. He has, in his familiar way, contradicted the experts in his Administration. The result is unnerving both for the experts and the public. Anthony Fauci, the director of the National Institute of Allergy and Infectious Diseases, is one of the officials who have tried to navigate doing their jobs properly and, at the same time, dealing with a completely unpredictable President. Fauci has openly, if subtly, clashed with Trump, telling him that it will likely take more than a year, not “a few months,” to develop a vaccine. “You should never destroy your own credibility. And you don’t want to go to war with a President,” Fauci told Politico. “But you got to walk the fine balance of making sure you tell the truth.” Fauci, who is seventy-nine, is a veteran of many major public-health challenges: AIDS, Zika, Ebola, and more. Of the coronavirus, he said, “I think that is going to be one of those things we look back on and say, ‘Boy, that was bad.’ ”

Public-health officials worry that the consequences of living with a President and a general disinformation universe that undermine facts and science could have increasingly dire consequences. He is serving no one well. When you see a Trump supporter at a rally telling a reporter for CNN that she doesn’t believe that coronavirus exists, that it is an invention of the political opposition, there are reasons for that thinking. And such disbelief in the facts might well lead such a person to inadvertently make bad decisions about her health and her family’s health.

Though there was much to criticize about China’s initial reaction to the outbreak of the virus, in Wuhan, Michael Mina, of Harvard, said that China has succeeded in slowing the spread by taking extraordinary measures, including travel shutdowns and quarantines of whole cities. “Without a clear signal of concern from the White House, people will continue going to big events and say to themselves that this virus might only hurt people over the age of eighty, not me and my family,” Mina said. “They won’t change their behavior in a way to help slow down this virus.”

Lipsitch, who also runs Harvard’s Center for Communicable Disease Dynamics, said that twenty to sixty per cent of adults will “eventually get this before it’s all over, but they won’t necessarily be symptomatic.” The strain on hospitals and public-health workers is bound to be tremendous. My colleague Ben Wallace-Wells attended a conference last week at Harvard’s School of Public Health and said that the capacity of even the best hospitals to deal with a pandemic was a matter of central concern to everyone there.