As the war in Iraq continues to rage, many in and outside government in the U.S. are left to wonder if it was possible to foresee the difficulty the United States is currently having with Sunni nationalists and Islamist insurgents. Recent American military experience offers significant insight into this question. With the fog of the Cold War finally lifting and clarity returning to the nature of conflict, the dominance of asymmetric warfare (where the belligerents use radically different weapons and tactics) in the military experience of the United States is all too evident. Lebanon (1982-1984), Somalia (1992-1994) and Afghanistan (2001-2004) offer recent and relevant insight into successes and failures of American attempts to fight adversaries utilising asymmetric conflict when it intervened in these three states. The results illustrate the difficulty of engaging adversaries unwilling to wage a conventional war and the need for improved strategic and tactical doctrine.