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This column has been updated to reflect news developments.

On Jan. 24, Richard Burr, a Republican senator from North Carolina, attended a private Senate briefing from senior government scientists about the seriousness of the coronavirus. Kelly Loeffler, a Republican senator from Georgia, received the same briefing.

At the time, many Americans did not yet understand the danger that the virus posed. The same day as the briefing, President Trump — in one of his many attempts over the past two months to make the virus seem like a frivolous matter — tweeted, “It will all work out well.”

Given the disconnect between what they knew and the public’s understanding, Burr and Loeffler had an opportunity to sound the alarm. They could have broken ranks with other congressional Republicans and told the country to take the situation more seriously. They could have criticized Trump for not doing more. Such criticism, coming from Trump’s own party, would have received major attention. It would have had the potential to alter Trump administration policy and, by extension, the course the disease took.