I like what Bill Cosby said about the possibility that Donald Trump, he of the weirdly sculpted hair and preposterous views, might run for president: “I don’t care.” But the fact that new polling of likely Republican primary voters finds the self-promoter tied with former Arkansas governor Mike Huckabee (17 percent each) just behind former Massachusetts governor Mitt Romney (21 percent) on their wish list for the 2012 GOP nomination deserves some scrutiny. It is tempting to say they’re all nuts. But the more likely rationale for anyone to say “I want Trump to be president of the country” is...