Anecdotal, but-
I was somewhere in the Midwest a few years back cornering a BKFC fight (not my favorite, but money is money) and I woke up early fight day to take a walk and get my head right.
It was a mid sized city somewhere and it all looked so run down and shabby. Crappy old cars, buildings falling over, long expired billboards, houses in disrepair. It sort of hit me in that moment; I was in America’s heart land surrounded by people who are truly and deeply patriotic. They believe that a God had ordained their country to be the greatest. That America was inherently superior to other countries around the world. But they look around and things don’t feel great. They definitely didn’t look great. so when a New York City billionaire real estate mogul hits the scene and tells them that they’re right, America ISNT great but he’s going to make it great again. He’s going to tell them who to blame- immigrants, trans people, the college educated- people foreign to them.
That is how and why Trump could get so many supporters from the degraded slump of the middle of the country. He can make all these big promises and they are desperate enough to put their hopes in him to literally make America great again.