MICHAEL Moore's new film "Sicko," a critique of the U.S. health-care system and paean to socialized medicine around the world, premiered amid great fanfare at Cannes last month. Time magazine reviewer Richard Corliss rejoiced, "The upside of this populist documentary is that there are no policy wonks crunching numbers." Wouldn't want anyone messing up Moore's fantasy with . . . facts. The American health-care system undeniably has serious problems, and Moore effectively dramatizes the suffering of people caught up in them. Yet he often exaggerates those problems. For example, he frequently refers to the 47 million Americans without health insurance,...