By 1979, John Lennon had become embarrassed of his former radicalism and had become a closet Republican, according to Fred Seaman, who was his assistant at the time:
John, basically, made it very clear that if he were an American he would vote for Reagan because he was really sour on Jimmy Carter.
He’d met Reagan back, I think, in the 70s at some sporting event… Reagan was the guy who had ordered the National Guard, I believe, to go after the young demonstrators in Berkeley, so I think that John maybe forgot about that… He did express support for Reagan, which shocked me.
I also saw John embark in some really brutal arguments with my uncle, who’s an old-time communist… He enjoyed really provoking my uncle… Maybe he was being provocative… but it was pretty obvious to me he had moved away from his earlier radicalism.
He was a very different person back in 1979 and 80 than he’d been when he wrote Imagine. By 1979 he looked back on that guy and was embarrassed by that guy’s naivete.
(Hat tip to Samuel Lenser.)