Why did counterculture icon Ken Kesey and the hippies (also known as “freaks” and “heads”) turn their backs on the political movement and methods of Leftist activists like Jerry Rubin and the Students for a Democratic Society (SDS)?

Why did counterculture icon Ken Kesey and the hippies (also known as “freaks” and “heads”) turn their backs on the political movement and methods of Leftist activists like Jerry Rubin and the Students for a Democratic Society (SDS)?