But from the beginning, the poisonous seed of homegrown anti-Americanism was present. It was present in the crop of ridiculous 9/11 conspiracy theories supported by certain celebrities, academics and politicians. It was present in the immediate condemnation of military action in Afghanistan. It was present in the reflexive self-criticism of the extreme left, which suggested that 9/11 was the foreseeable result of xenophobic American foreign policy. And over time, that seed grew. As Americans grew weary of war without immediate victory and the long-term task of reshaping the Middle East, the seed sprouted into full flower. Now, on the sixth anniversary of the September 11 attacks, the most important ideological battle -- the battle to define America's aims and self-image -- is between those who see America as the perpetrator of racism and violence and those who see America as a force for good in the world. The ideological battle is the battle to define the lessons of 9/11. On one side stands the Vietnam-era left, which blames the United States (and in particular, its support for Israel) for the attacks of 9/11 and suggests that the American response to 9/11 demonstrated our boorish egocentrism and bigoted misinterpretation of world politics. On the other side stands the right, which sees Islamism, not American exceptionalism, as our true enemy. In the center, wavering, stands the bulk of the American people. The legacy of 9/11 remains in doubt. A century from now, 9/11 will be seen either as the death knell of a crumbling civilization or a rallying cry for a renewed, American-led movement for freedom. The choice remains in our hands.