Serious people feel an obligation to listen whenever Barack Obama speaks. They furrow their brow and hold their chin and parse every word. They assume that most everything a president says is significant, which is true. They assume that what's significant must also be well-informed. Not necessarily.

I've been thinking about this as it becomes clear that, even at an elementary level, Mr. Obama often doesn't know what he's talking about. It isn't so much his analysis of global events that's wrong, though it is. The deeper problem...