This effort has also refocused attention on an older—but no less potent—enemy: Communist subversion. Cuba, of course, brings us back to President Kennedy. He praised some American labor unions for ridding themselves of Communist subversion. What You Can Do to Oppose CommunismKennedy hammered away at the threat of Communist subversion in the first minutes of his presidency. On the day of his assassination in Dallas, President Kennedy was ready once again to warn about subversion.