The U.S. Postal Service itself has warned states it cannot guarantee that all ballots cast by mail for the Nov. 3 election will arrive in time to be counted, even if ballots are mailed by state deadlines. That is raising the possibility that millions of voters could be disenfranchised.

It’s the latest chaotic development involving the agency, which has found itself in the middle of a high-stakes election year debate over who gets to vote in America, and how. These questions are extremely important in the middle of the Coronavirus pandemic.