The U.S. has never really managed to get coronavirus testing right for any extended period of time, and now we're entering a new phase of potential dysfunction.

Driving the news: Democrats and some health care experts are livid over the Centers for Disease Control and Prevention's latest change to its testing guidelines, which now recommend against testing for asymptomatic people.

• It's a flashback to the spring, when the U.S. could only perform a tiny number of tests and reserved them for the sickest patients.
• It was true then, and remains true now, that an ideal testing strategy would not exclude asymptomatic people. Some 40% of all cases are asymptomatic, meaning a whole lot of people are likely spreading the virus without knowing it.

Between the lines: The U.S. is now conducting some 690,000 tests per week, but it still hasn't been enough to keep up with demand, causing delays of up to two weeks for test results — which renders them all but useless.

• Cutting back on testing is a way to ease those backlogs, but at the cost of missing some infections.
• Testing was declining even before the CDC revised its guidelines. It fell by about 5% over the past week.

The intrigue: Sources told multiple news outlets that the White House pressured the CDC to revise its guidelines. Brett Giroir, the Trump administration's "testing czar," said that wasn't true, and that the revisions came from the CDC and the White House's coronavirus task force.

• But Anthony Fauci, a prominent member of that task force, told CNN, "I was under general anesthesia in the operating room and was not part of any discussion or deliberation regarding the new testing recommendations."
• "I am concerned about the interpretation of these recommendations and worried it will give people the incorrect assumption that asymptomatic spread is not of great concern. In fact it is," he said.

What they're saying: The response to the change has been overwhelmingly negative.

• California Gov. Gavin Newsom said his state wouldn't follow the guidelines.
• The Association of American Medical Colleges called them "irresponsible" and "a step backward."
• "This is potentially dangerous ... I feel like this is going to make things worse," infectious disease physician Krutika Kuppalli told NYT.