“Though he lived for 40 years, Lennon’s reputation as a peacenik derives from just a brief period in the very late ’60s and early ’70s, when antiwar attitudes were practically de rigueur among the hip cognoscenti. Until then, he had largely kept quiet about politics. … The peace protests that Lennon is best known for probably were not even his own ideas; more likely, they were [Yoko] Ono’s.”