which, even though strongly acted on by environment, tends to lead to conservative political orientation.
You are sadly right that the "traditional" conservatism developed in the middle of last century is gone from the Republican Party. Right-wing extremist leaders have purged almost all who believe in protecting what has worked well in favor of installing extremists and mountebanks who will cooperate in destroying what has worked well. But this started before the Kochs created the tea party movement out of a largely clueless unhappiness among conservatives--over exactly what they and those like them were doing. (Scheming bastards!)
Interestingly, conservatism doesn't have a centuries-old intellectual basis and only coalesced as an actual political orientation in the U.S. as a "gut"reaction to the New Deal era and growing cold war. Unwilling and/or unable to differentiate between the inherently Constitution-supporting (anti-authoritarian!) liberalism of New Deal leaders and the authoritarian absolutism characteristic of far left movements, they came together over fears that we were developing into a Russia-style authoritarian state.
Then and since, many have tried to give this huge political movement a desperately needed basis in intellect--which notably would provide at least some of the stability of principle liberals are blessed with--but as we can see, authoritarian leaders who've learned to tap into the "gut" feelings and urge to follow of mostly authoritarian-leaning conservatives have been leading half a nation just about any direction they want.
But innate conservatism in various types, mixtures and strengths, traditional/temporal, social/religious, economic/libertarian, is very alive and currently energized and will always be a big part of us.
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