The problems with the U.S. occupation in Iraq have been documented and debated extensively, but primarily at a strategic level—from a bird’s-eye view. Analysts have focused on weaknesses in prewar planning and subsequent unfortunate high-order decisions: insufficient U.S. and allied troop levels, excessive de-Ba‘athification and the summary disbanding of the Iraqi army among them. While these strategic considerations have shaped—and have probably doomed—the operation, analysis so far has neglected the crippling lack of capability at the tactical and operational levels—the worm’s-eye view.

This is a mistake, because even if prewar planning had focused wisely on the right things, and even if no strategic errors had been made, the United States and its allies would still be foundering in Iraq. Getting the strategic elements right are necessary but not sufficient conditions for policy success. It’s not enough to have a blueprint if you want to build a shed or a new patio deck. You need to have the right tools, too, and know how to use them.