Editor’s Note: Jonathan Reiner, MD, is a CNN medical analyst and Professor of Medicine and Surgery at George Washington University. The views expressed in this commentary belong to the author. View more opinion at CNN.

CNN  — 

The January 6 attack on the United States Capitol was a vivid demonstration of the havoc that can result when a really big lie is repeatedly injected into the body politic.

Jonathan Reiner

But there was another big lie in 2020, also propagated by former President Donald Trump, involving the coronavirus pandemic. It was a lie that systematically downplayed the severity of Covid-19 and the utility of face masks. It very likely resulted in the unnecessary deaths of hundreds of thousands of Americans.

To understand the genesis of this lie, remember that the coronavirus arrived in an election year. Despite a rancorous initial three years punctuated with an impeachment, the former president’s path to reelection was bolstered by one unimpeachable accomplishment: a robust economy. The coronavirus threatened that. The resulting interplay between politics and the pandemic created an irresolvable conflict that influenced the Trump administration’s coronavirus response for the remainder of his term.

On January 22, 2020, the day the US reported its first case of Covid-19, President Trump said he wasn’t worried about the outbreak becoming a pandemic. “We have it totally under control,” he said.

In his book “Rage,” Bob Woodward reported that six days later, National Security Adviser Robert O’Brien unambiguously told Trump: “This will be the biggest national security threat you face in your presidency. This is going to be the roughest thing you face.” On Febuary 7, 2020, Trump told Woodward the coronavirus was highly lethal, noting that it was “more deadly” than – “even your strenuous flus.”

On February 25, four days before the first report of an American coronavirus death, Dr. Nancy Messonnier, the head of the US Centers for Disease Control and Prevention’s National Center for Immunization and Respiratory Diseases, informed reporters that she had told her children that “we as a family ought to be preparing for significant disruption to our lives.”

That same day, Alex Azar, then Department of Health and Human Services Secretary, assured the press that the Trump administration was committed to “radical transparency.”

The next day, the President said: “This is a flu. This is like a flu. It’s a little like a regular flu that we have flu shots for. And we’ll essentially have a flu shot for this in a fairly quick manner.”

On March 9, with US coronavirus deaths mounting, Trump again likened the coronavirus to the flu, tweeting, “So last year 37,000 Americans died from the common Flu. It averages between 27,000 and 70,000 per year. Nothing is shut down, life & the economy go on. At this moment there are 546 confirmed cases of CoronaVirus, with 22 deaths. Think about that!”

Despite the knowledge that the virus was being spread via respiratory droplets and aerosols, the CDC was slow to recommend masks for the public. On February 29, Surgeon General Jerome Adams scolded the public in a tweet: “Seriously people- STOP BUYING MASKS! They are NOT effective in preventing general public from catching #Coronavirus, but if healthcare providers can’t get them to care for sick patients, it puts them and our communities at risk!”

On April 3, the CDC changed its position, and advised all Americans to wear a face covering in public. At a Coronavirus Task Force briefing that day, the President immediately threw cold water on the recommendation, declaring: “You can do it. You don’t have to do it. I’m choosing not to do it, but some people may want to do it, and that’s OK.” He added, “Wearing a face mask as I greet presidents, prime ministers, dictators, kings, queens – I just don’t see it.” The message to his followers was clear: masks were optional.

Despite Trump’s public nonchalance, in private he had known for months precisely how easily the virus was spread, and the rationale for wearing masks. On February 7, he told Woodward: “It goes through air, Bob. That’s always tougher than the touch. You know, the touch - you don’t have to touch things, right? But the air, you just breathe the air. That’s how it’s passed. And so that’s a very tricky one. That’s a very delicate one.” On April 13, Trump told Woodward that the coronavirus was “so easily transmissible, you wouldn’t even believe it.”

For Trump, however, there was no going back, and it would be another three months before he agreed to wear a mask in public. During a July 12 visit to Walter Reed National Military Medical Center, Trump told reporters, “I’ve never been against masks, but I do believe they have a time and a place.” But the damage had been done, and like wearing a red MAGA hat, refusing to wear a mask in public became a sign of fealty to the president. Masks had been politicized.

In July a Gallup poll found that 94% of respondents registered as Democrats always, or very often wore a mask vs. only 46% of Republicans. Likewise, many Republican Governors, fearful of risking a presidential rebuke, or backlash from his supporters, refused to issue mask mandates. Gov. Kristi Noem of South Dakota said: “There are many others who question the effectiveness of masks … As I’ve said before, if folks want to wear a mask, they should be free to do so. Similarly, those who don’t want to wear a mask shouldn’t be shamed into wearing one. And government should not mandate it.”

On Fox News in March, Tucker Carlson said: “Of course, masks work. Everyone knows that. Dozens of research papers have proved it.” By fall, he was openly mocking mask mandates and the science supported them. “What they’re really telling you is that masks are magic,” he said. “What appears to be a flimsy face covering is, in fact, a holy amulet that protects us from disease.”

With the election looming, Trump resumed his trademark large campaign rallies. Among the attendees at the first event held on June 20 in Tulsa was the former presidential candidate Herman Cain, who was photographed sitting unmasked in the tightly packed crowd of 6,200 similarly unmasked attendees. One week after the rally, Cain tested positive for the coronavirus. Two days later, Cain tweeted support for Noem’s decision not to require masks at Trump’s planned visit to Mount Rushmore. “Masks will not be mandatory for the event, which will be attended by President Trump. PEOPLE ARE FED UP!” Cain died of coronavirus one month later.

During the summer, with deaths mounting, Trump sidelined his principal coronavirus advisers and brought in the Hoover Institute’s Scott Atlas, whose libertarian theories were more aligned with the Trump’s public declarations than those of his existing team including Anthony Fauci and Deborah Birx. Atlas publicly doubted the efficacy of masks, tweeting in October: “Masks work? NO: LA, Miami, Hawaii, Alabama, France, Philippnes, UK, Spain, Israel. WHO: ‘widesprd use not supported’ + many harms.”

As the election approached, so did the pace of the then-president’s rallies, which were crowded, mask-optional events. A Stanford University study estimated that 18 of these campaign events likely resulted in more than 30,000 coronavirus cases and 700 deaths.

On September 26, the White House held a Rose Garden event to announce the nomination of Amy Coney Barrett to the Supreme Court. Again, masks were not required, and very few attendees wore them. Five days later, the President and First Lady tested positive for the coronavirus. The next day Trump was taken via helicopter to Walter Reed.

His three-day hospitalization gave him an opportunity to recraft his coronavirus message. He didn’t. In a recorded statement from the hospital, Trump said: “Don’t let it dominate you. Don’t be afraid of it.” Upon his return to the White House, the President made a show of walking up the curving steps to the Truman Balcony. As he stood facing the South Lawn, the former president dramatically removed his mask, saluted Marine One, and then turned and, actively infected with the coronavirus and unmasked, he entered the Executive Residence.

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Three weeks later, the University of Washington’s Institute for Health Metrics and Evaluation issued what would turn out to be an astonishingly accurate prediction. IHME estimated that there could be 500,000 US deaths by the end of February. Their analysis also suggested that 130,000 of these deaths could be prevented if the country adopted universal masking.

Dr. Christopher Murray, the Institute’s director said, “We think the key point here is that there’s a huge winter surge coming.” Murray and his colleagues were spot on, but still there was no Trump administration push for universal masking.

When asked this past fall why he didn’t tell the truth to the American public the then-president replied, “I don’t want people to be frightened. I don’t want to create panic… And certainly, I’m not going to drive this country or the world into a frenzy.”

As predicted, this week the US surpassed half a million deaths. The Greek tragedian Aeschylus wrote, “In war, the first casualty is truth.” When the history of the American war against the coronavirus is finally written, historians will note that Donald Trump’s big lie about masks was the original sin.