The modern conservative movement did begin in the Eisenhower years and received its intellectual rationale from William Buckley's 'National Review.' The movement took a hit from the Goldwater campaign and defeat, but got back on track during the Reagan years. Gingrich and the shutdown of the government that he engineered marked a devolution from the conservative movement, a detour from the principles of mainstream conservatism.  It's been downhill from there: the rise of the religious right; the Tea Party (or Parties); the blatant racism of the birtherism drivel; the alt-right; culminating in the nomination by the Republican party of an unabashedly fascist, racist know-nothing blowhard.  This is not something that happened overnight; and it was not a stealth operation. It happened in full view and was aided and abetted by the cowardly acquiescence of the putative Republican "leaders." In Trump, the Republicans are reaping what they sowed and getting what they deserve.