Trump's single biggest mistake in the 2020 campaign

[Southern Senator North Carolina Yankee]

I agree with Pericles.

There is something I call the Commander in Chief test, used to be referred to as the red phone ("Red phone is ringing in the White House, who do you want answering it?"). In this context, Covid was the red phone and Trump's erratic statements failed to project the kind of stable leadership you want in a crisis situation.