Do you want me to explain it to you? It's a pretty long story. Technically it starts in 1672, but I can skip ahead a little.
Back in the 1940s and 1950s there was this group of academics in Chicago, who wrote about really unpopular economic theories. See, at the time, most scientists thought the question of macroeconomics had already been solved, by a guy named Keynes - he had answered a lot of difficult questions about the Great Depression, and his policy recommendations were extremely effective during America's recovery. Those Chicago economists didn't like Keynes much, though. They believed that instead of spending money to buy real things, governments could stimulate the economy the same way by buying and selling bonds. That way, private businesses are free to decide how economic stimulus should be spent, and the government can more easily claw it back after a recovery.
Many of these economists helped FDR administrate the New Deal, and in doing so, made friends in the right places. They found a sympathetic ear in the Republicans of the day, and eventually rose to become the economic thought leaders of the party. Those Chicago economists were eager to learn if their frequently-disputed beliefs were correct, and used their political sway to attempt economic engineering under Nixon. This first attempt included, among other things, the repeal of the gold standard. These policies were deeply unpopular and ineffective, and Nixon quickly retreated back to the safety of mainstream economics, but not before inflicting an economic wound that researchers today blame for stagflation nearly a decade later.
The Chicago economists reasoned that their experiment didn't fail because their ideas were bad, but rather that mainstream economic ideas were simply too good for the average American. Keynes's ideas caused immediate gains that benefited the poorest people the most, through infrastructure spending and government job creation. There was wailing and hand-wringing; the Chicago economists feared that the mainstream economists advising the Democratic party were trying to silence their dissent with thinly-veiled vote buying. The new Republican ideas were centered upon stimulating the biggest private sector firms, an agenda that simply wasn't attractive to most voters.
The Republicans found their spoonful of sugar in the Dixiecrat/demographic shift. The shift brought principally racist and/or anti-federalist voters over to the Republican party. This wasn't out of support for Chicago economic stewardship, but simply because the Republicans were opposite the Democrats. This complete evacuation of common sense hit a fever pitch in 1979, when Jerry Falwell, incensed about who-gives-a-****, founded a Christian voting bloc in direct personal opposition to Jimmy Carter. It all happened for the stupidest possible reasons, but the Chicago economists had finally found the subjects for their grand experiment. It began promptly upon the election of Ronald Reagan, and continued unabated until about a couple of months ago when the Federal Reserve conclusively demonstrated that none of their ideas work.
In the meantime, though, the Faustian bargain - the union between heterodox economics and the justly marginalized - ate the Republican party alive. These disparate blocs were never married to the core conservative ideals of the Republican intelligentsia: one mistake, and they would punish the Republican party just as they did the Democrats. The Republicans were forced to adopt increasingly erratic social policies in order to appease those blocs, and they had to couch their economic engineering in acceptable and understandable language. The quiet dignity of Eisenhower was no longer permitted; Republicans needed to be white, Christian businessmen, with the stage presence of an evangelical minister. The last plausible Republican presidential candidate was stuck so deep in this mess that he affected a bumpkin accent for 8 straight years.
Oof. Still with me? Great.
So, about Trump. You see, Trump isn't just running as a Republican, he is running as The Republican. Trump is playing the character for whom the base has been trained to vote. He is the perfect candidate: rich; white; extensive business experience; angry; racist; unapologetic; larger-than-life. Is he actually a Republican? Does he believe in desegregation, or monetarism, or supply-side stimulus? Absolutely not. But none of that matters. The racists, the anti-federalists, and the Christians were never voting for Chicago economists. They were voting for the anger, racism, fear, and pontification, and that's exactly what Trump is offering them. So the Republican party is now in full meltdown mode, and every politically conscious Republican is tearing their hair out, because up until now none of them realized that their entire movement permanently died decades ago.