Not sure I agree with your views on “world peace.” Trump has threatened to go to war with Mexico multiple times if they don’t control their cartels. He’s also threatened Iran.

I’m also not sure I agree with your views of history. Reagan called the Soviet Union the “evil empire.” He was not just “friends” with Gorbachev. Both Bushes led us into forever wars in the Middle East. Yes, they had bipartisan support but had it not been for Collin Powells presentations on WMDs the second Iraq war wouldn’t have started.

Also, republicans have flirted with Trump style isolationism before. Look at the rhetoric from many rich businessmen like Henry Ford prior to WWI and WWII. Many political scientists and historians argue that America slow-walked the world into both wars by refusing to take definitive stands, first against the Kaiser and then against Hitler. The world tried to appease aggressive dictators like Putin (revisit what happened in Munich in 1938). It didn’t bring world peace as you described - it only emboldened Hitler and others and led to world war.

Isolationism has never worked throughout history and there’s no reason to believe Trump - with no diplomatic experience who only thinks of his own self interests - will magically make it work in the 21st century, whether in Ukraine or Gaza.