How did Trump divide the country?
Perhaps he didn't overtly divide the country, but he had many opportunities to try to bring the left and the right closer to each other. Not the far left, because they want to remain divided, they thrive on division.
What Biden is doing is nuts, because here's actually dividing the left from the far left, and pushing the left toward the right. Don't get me wrong, I think that's great for Republicans, but I think Trump could have reeled in some of the left himself by just acknowledging that not everybody on the left is AOC crazy.