The more extreme side always wins out and eventually the country.
Just going back to Reagan, mainstream Republicans initially scoffed at supply-side economics. George Bush Sr called it voodoo economics. He was right, but Reagan won. Not only that, Bill Clinton's Democratic Party followed suit.
Then came the neocons. I don't have to tell you how the neocons took control of not just the Republican Party, but also the Democrats as well. Has neoconservatism retreated? If you think so, AIPAC would like a word with you. The first time I heard of neocons was from National Review. The NR writers were unanimously against them. The mag completely changed their tune later.
Then came MAGA. Remember those "Never Trumpers"? The rest is history.
The more extreme side always wins. Or rather, the more racist side always wins. Then Democrats capitulate.
I have to wonder if mainstream Republicans put up a fight against Nixon's southern strategy. Probably not. The racists always win.