The mood in the Capitol was already dark. Then came Omicron.

Across the country, the omicron variant has sent coronavirus infections into the stratosphere. Winter weather and empty shelves have turned moods surly. Americans have turned on each other over vaccinations, mandates and masks.

And at the U.S. Capitol, where all manner of people are thrown together in an unhappy stew, the moment was crystallized this week in a hot-mic episode. In an audible whisper, Dr. Anthony Fauci, the government’s top infectious disease expert, summed up his feelings for another physician, Sen. Roger Marshall, R-Kan.