Interestingly, there was a documentary recently shown on BBC4 - "How The Beatles Helped Bring Down The Berlin Wall" - which purported to show how the popularity of their music helped, in its own way,to undermine the politics of the Eastern bloc. Whether this was all true or not, I can't say, but the banning of the "anodyne" Beatles may have been because their musical power was recognised as subversive - in Communist terms.