The extreme RW is mainstream
We turned control of our economy over to a man who was, in his younger days, an inner sanctum member of Ayn Rand's Objectivist society, and a foaming-at-the-mouth advocate of the gold standard as the only defense against the welfare state. (Fed Chair Alan Greenspan)
We turned the judicial branch over to a man who, in his younger days as a clerk to a Supreme Court justice, advised not only upholding "separate but equal" in Brown, but using Brown as an opportunity to overturn Plessy v. Ferguson. (Chief Justice Rehnquist, who was almost joined on the SCOTUS by Bork, the man who fired Archibald Cox.)
We turned stewardship of federal lands over to a man who thought Jesus was returning soon, so conservation made no sense. (Watt.)
We turned the nuclear launch codes over to a man who was a public laughing stock in 1976 as being a senile ultra-nationalist Bircher news-letter level segregationist, and who kicked of his campaign in Philadelphia, Mississippi, to celebrate the most infamous mass lynching of civil rights activists. (Reagan.)
And all of that was before the Republican party became extreme!