For Donald Trump, who'd spent weeks celebrating hydroxychloroquine as a silver bullet in the fight against the coronavirus, yesterday was not a great day. In the morning, the public was confronted with this Associated Press report:

A malaria drug widely touted by President Donald Trump for treating the new coronavirus showed no benefit in a large analysis of its use in U.S. veterans hospitals. There were more deaths among those given hydroxychloroquine versus standard care, researchers reported.

A few hours later, an NPR report went even further.

A panel of experts convened by the National Institute of Allergy and Infectious Diseases recommends against doctors using a combination of hydroxychloroquine and azithromycin for the treatment of COVID-19 patients because of potential toxicities.... The recommendation against their combined use would seem to fly in the face of comments made by President Trump suggesting the combination might be helpful.

On March 21, Donald Trump declared via Twitter that the combination of hydroxychloroquine and azithromycin has "a real chance to be one of the biggest game changers in the history of medicine." Exactly one month later, on April 21, U.S. researchers concluded that the combination of hydroxychloroquine and azithromycin increases the risk of sudden cardiac death.

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At yesterday's White House press briefing, the president had to know he'd face questions about this, and he was. "I don't know of the report," Trump said. "Obviously there have been some very good reports and perhaps this one's not a good report -- but we'll be looking at it."

That wasn't much of a response. As we discussed yesterday, the president didn't just express tacit support for hydroxychloroquine; he effectively became an infomercial pitch-man in support of an unproven medicinal treatment. Based on "a feeling" he said he had, Trump publicly encouraged Americans to start taking the medication -- "Take it," Trump said, adding, "I really think they should take it" -- adding that he personally was prepared to start himself on the drug.

Others on his team echoed the line, including Attorney General Bill Barr, who praised hydroxychloroquine as a "very promising" treatment, and who chided journalists for waiting to see scientific evidence and clinical research.

And then, of course, there's Fox News, where several on-air anchors could barely contain their enthusiasm for the medication. At one point, a prime-time Fox News host went so far as to personally introduce the president to doctors who talked up the potential benefits of hydroxychloroquine.

And now, all of a sudden, Trump and his allies are scaling back the hype.

I imagine some on the right will downplay the importance of this, suggesting that there's no real cost to a president and his team investing hope in a possible treatment, even if it was premature, and even if the preliminary research suggests the treatment may be ineffective.

But Team Trump didn't just cross their fingers and hope for the best. The president urged Americans to start taking the medication, creating a run on pills that some people actually needed. What's more, Politico reported that some health officials are "being pulled away from other potential projects to address the president's hunch." The article quoted an HHS official who lamented the "time and energy being soaked up by a potential wild-goose chase."

Soon after, Politico published a related report, noting that career health officials had raised behind-the-scenes warnings about hydroxychloroquine, but they'd been "warned not to publicly speak out and potentially contradict Trump."

There were also literal investments, as the administration put millions of doses of the drug into an emergency stockpile.

It would appear some folks have some explaining to do.