It’s actually hard to ever really know. He did also say at one time though that he preferred the Tories to the Labours because they “let me keep my money.”
So who knows? It almost seems it would have been a natural evolution for a guy like him...in the 60s he was suspicious of “The Man” who, at the time, was regarded as a war mongering capitalist pig. However, by the late 70s it was clear that “the Man” was really the entrenched leftism that had overtaken the US government.
For a man who was afraid of the “Man”, he ended up donating a lot of cash to the NYPD for vests and equipment. There are more signs that he was not anywhere near the peacenik radical that the left paints him as. The NYPD love the guy back in the day.