Joe Biden became America’s president in 2021 because the alternative was four more years of Donald Trump. If Ronald Dion DeSantis, who has announced his candidacy on Twitter today, wins the Republican party nomination next year, it will also be because the alternative is you-know-who. Trump fatigue is a real phenomenon: even many Trump supporters think it’s time to move on, which is the key to the 44-year-old DeSantis’s appeal.