Trump plays this way because he knows and cares so little about the issues. The country has problems because our leaders are stupid. He's going to fix them because he's a winner. He's going to make America great again by p*****g on foreigners. The problems are simple, and life will be good again when we have a leader who sweeps them all away with a flick of the wrist.
The interesting thing IMHO is that Trump supporters, in my experience, generally understand that Donald's rant is nonsense, AND THEY DON'T CARE. They think the country is going down the tubes, but rather than think about it, they are content to follow a ranter. If engaged civilly, which is always my practice, they will readily agree that the left isn't stupid. The other sides knows exactly what it is doing. We have fundamental moral and philosophical divisions about the nature of the country in which we want to live and the relationship of citizen and state. Do we want a free society, will we defend freedom of speech and religion, are we willing to hold people responsible for their actions, and should government be the servant or the master? The left no longer accepts the fundamental American civic and constitutional settlement. Most Trump supporters I've spoken with seem to understand this. But they don't seem to care that Trump himself doesn't seem to. That's disturbing.
This is why it scares me because should the day come we should ever be invaded half the population would welcome them with open arms