I remember, around 1960, my father came home with a pamphlet from the John Birch Society. That weekend he and a friend discussed it, laughing frequently at it's absurdities. My dad and his friend had grown up during the Great Depression, and served, at the 'sharp end' in WWII. At the time both voted pretty much for Republicans.
At the last CPAC 'convention' the Birchers were honored participants, and virtually 'moderate' compared to many of the others there. I know that Nixon's 'southern strategy' , with it's 'dog whistles', had brought a boatload of red neck racists into the Republican party, and old Ronnie, with his phony charm and folksy front, had 'sealed the deal' for the south to be Republican, But where did the teahadists surface from? The sight of the angry crowds trying to bar the entry of refugee children to temporary shelter left me shocked and sickened (and angry). Even the surviving old time Republicans, who used to say sensible, helpful intended things have become snarling beasts, parroting the hateful untruths and distortions of the vilest liars and bigots of the Right.