MOST libertarians don’t like their name. “It’s a clunky neologism with too many syllables,” admits David Boaz of the libertarian Cato Institute. Charles Murray agrees. It’s “etymologically” imperfect, he says in his new book on the subject. And yet, the word and the movement persist, indeed flourish.  From modest beginnings in the 1950s when a few free-market intellectuals began calling themselves libertarians, it has grown into a movement with a party, a presidential candidate, self-professed columnists, the now-requisite Hollywood stars (Kurt Russell), and—most important for any serious political philosophy today—a think tank in Washington, D.C.