When American airpower played such a central role in driving Iraq's occupying forces from Kuwait in early 1991, many doubters of its seemingly demonstrated capacity to shape the course and outcome of a major showdown independently of ground action tended to dismiss that remarkable performance as a one-of-a-kind force employment anomaly. It was, the doubters said, the clear and open desert environment, or the unusual vulnerability of Iraq's concentrated armored formations to precision air attacks, or any number of other unique geographic and operational circumstances that somehow made the Persian Gulf War an exception to the general rule that it takes "boots on the ground" in large numbers, and ultimately in head-to-head combat, to defeat well-endowed enemy forces in high-intensity warfare