The second factor was Trump. On July 6, he tweeted, “SCHOOLS MUST REOPEN IN THE FALL!!” The next day, at a White House event, the president said, “We’re very much going to put pressure on governors and everybody else to open the schools. It’s very important for our country. It’s very important for the well-being of the student and the parents.”
In this case, Trump happened to be right; it was important. But by this late stage in his presidency, most Democrats assumed that anything he said was a lie. If Trump said schools should reopen, that was reason enough for them to assume they should stay closed. The sense that opening up was a Trump-endorsed policy seems to have energized opposition to it in blue America — even as data accumulated that the harm being done to the country’s children outweighed any potential benefit.