In the aftermath of the recent Persian Gulf Conflict, many of us who remembered Vietnam celebrated that we had finally shedded the stigma of that war. Indeed, the nation's frustrations at not winning the Vietnam war had resulted in numerous efforts to explain "what went wrong ..." Strategists and other experts found it difficult to explain how a nation, regarded as the most powerful in the world, had wilted under the tremendous pressures of negative public sentiment created as a result of the protracted war. Finally in 1981, Colonel Harry G. Summers wrote the first creditable critique of the war in his book, On Strateqy: The Vietnam War in Context. Using Clausewitzian theory, Colonel Summers describes in clear terms how our national policies and military strategies failed us. The purpose of this paper is not to revisit lessons learned from Vietnam. Instead, my intent is to use Clausewitz's theory to help "clarify concepts and ideas" which explain our successes in the Persian Gulf. It is my thesis that these successes are in large measure attributable to our understanding and application of this theory in the post-Vietnam period and during the Persian Gulf Conflict. To accomplish this, i will look first at Clausewitz's concept of the "Trinity" and discuss the role each element played during the conflict. Secondly, I will look at the conduct of the war in the context of his theory, examining our "preparations for war" and actual combat or "The Engagement." Finally, I will critique the effectiveness of the theory to address contemporary issues of war, and it's relevance in terms of lessons learned for the future.