Seven weeks ago today, Donald Trump visited the CDC offices in Atlanta, where a reporter asked the president how hospitals can best prepare for the escalating coronavirus crisis. Trump's answer rambled a bit, before he assured everyone, "I like this stuff."

The president added, in apparent reference to epidemiology, "I really get it. People are surprised that I understand it. Every one of these doctors said, 'How do you know so much about this? ' Maybe I have a natural ability."

We were reminded again yesterday that Trump does not "really get it," does not "understand" science or public health, and most certainly does not have "a natural ability." This was the pitch the president brought to the public during yesterday's White House briefing:

"Supposing we hit the body with a tremendous -- whether it's ultraviolet or just very powerful light -- and I think you said that hasn't been checked but we're going to test it. And then I said supposing you brought the light inside the body, which you can do either through the skin or in some other way, and I think you said you're going to test that too. Sounds interesting. And then I see the disinfectant that knocks it out in a minute, one minute. And is there a way we can do something like that by injection inside -- or almost a cleaning. As you see it gets in the lungs, it does a tremendous number on the lungs, so it would be interesting to check that.... It sounds interesting to me. So we'll see."

Get the msnbc newsletter. This site is protected by recaptcha

In context, the briefing had just featured comments from William Bryan, who heads the Department of Homeland Security's science and technology office, who spoke about tests involving sunlight and disinfectants. This apparently gave the president some ideas about internal lights and the possibility of "injections."

As an NBC News report added, medical professionals "reacted with horror" to Trump's comments, and with good reason.

It never occurred to me that a presidential briefing might necessitate "do not try this at home" warnings. And yet, here we are.

My concern is not that Trump, whose ignorance remains unsettling, has no idea what he's talking about. Rather, my concern is that there are many Americans watching his briefings who may not realize the president has no idea what he's talking about.

This is more than a hypothetical. Nearly a month ago, an Arizona couple saw Trump discuss the potential benefits of chloroquine during a televised briefing. They took the medicine, became extremely ill, and one of them died.

Common sense suggests a president would learn of a tragedy like this one and learn the importance of caution and restraint when addressing the public during a public-health crisis. Trump, however, can't seem to help himself.

I have no idea if anyone will start experimenting with disinfectants because they saw their president on television, but if even one American poisons themselves because of Trump's ridiculous comments, it will be one too many.

I try to watch just about every White House pandemic briefing, and I tend to cycle through a variety of predictable emotional reactions. The president's antics are, at various times, exasperating, maddening, and depressing.

Yesterday, however, Trump made matters considerably worse, becoming menacing and dangerous.