What did Donald Trump do today?

He probably figured out that virus tests test for viruses.

Today, after tweeting that testing for COVID-19 was a "double-edged sword" because diagnosing sick people made his administration look bad, Trump appeared at White House event on senior citizens.

Referring to that COVID-19 testing, Trump told attendees that "if we stop testing right now, we’d have very few cases, if any."

One possible interpretation of this is true, as far as it goes: Trump is correct that without diagnostic tests, there wouldn't be many diagnoses.

The problem with that is that literally every plan to combat the spread of the disease—including Trump's own—relies on the near-universal availability of free, accurate, and rapid tests. Getting that kind of infrastructure off the ground in a country the size of the United States is difficult and expensive, which appears to be why Trump has insisted it's not something he needs to take any responsibility for. 

One frequently cited benchmark for the number of tests needed to contain the virus without imposing stay-at-home orders is 5 million per day. Trump claimed on April 28 that the country would hit that mark "soon." Six weeks later, the United States manages about 500,000 tests per day.

The other explanation for this remark is that Trump was briefly confused into thinking that testing somehow causes COVID-19. As alarming as that would be, it wouldn't be unprecedented. Trump has also mused out loud about using flu vaccines as a drug to treat the novel coronavirus, to say nothing of household cleansers.

Why should I care about this?

• This is way, way too important for Trump to be confused about or giving up on.

• Ignoring a problem doesn't make it go away, especially when the problem is a contagious disease.