Every presidency is the subject of competing caricatures. But almost a year into his first term, there’s something particularly elusive about Barack Obama’s political identity. He’s a bipartisan bridge-builder — unless he’s a polarizing ideologue. He’s a crypto-Marxist radical — except when he’s a pawn of corporate interests. He’s a post-American utopian — or else he’s a willing tool of the national security state.

The columnist's blog on politics and culture.

The press has churned out a new theory every week, comparing Obama to John F. Kennedy and Franklin Roosevelt, to George H. W. Bush and Jimmy Carter — to every 20th-century chief executive, it often...