According to the all-but-unchallenged conventional wisdom, the American people feel angry at the status quo and demand dramatic change. Why, then, do recent polls show public sentiment tilting toward the GOP "” the very party that's stubbornly resisting change? And why should so many voters express increasing distrust, and even resentment, of the ruling Democrats who've tried to deliver just the sort of sweeping transformations they thought the people craved? Hope and change, it seems, morphed quickly into fear and retrenchment.

This anomalous shift has less to do with the fickleness of public attitudes, or some sudden and unprecedented ideological awakening, than it does with chronic misinterpretation of popular dissatisfaction during periods of discomfort and...