Why is Biden happy about taking on Trump again?

I think Joe Biden and his campaign team have have got it into their heads that it's good news Donald Trump is going to win the Republican nomination because then the election will be all about dictatorship versus democracy. If only it were that simple. Judging by the fact that Trump waltzed towards a huge victory in Iowa over his Republican rivals, it doesn't seem to me as if American voters are worried one bit about dictatorship versus democracy. They just want Trump, autocratic warts and all. So, however much Biden goes on about the country facing a dangerous moment when democracy could be stamped on if he is not reelected as president, I fear that message might fall on deaf ears, certainly ears belonging to Trump's huge fan base. So, it seems a little optimistic to imagine that everyone will turn to Biden at the last moment because of the fear that Trump will dump democracy and become America's Mussolini. He may well do just that, but do people care? Iowa says no.