二○○一年九月十一日發生在美國的「911事件」，除讓杭亭頓在一九九三年提出的「文明衝突」論再度成為世人關注與應論的集合，也使得杭亭頓從冷戰以來即為美國外交政策與戰略設計的「策士」立場更為清晰。「文明衝突」論是杭亭頓在冷戰結束後為美國尋找新假想敵、鞏固西方統一戰線及重塑全球新戰略的一套思維。這套戰略思維因在「911事件」中強烈影顯美國(西方文明)與回教激進團體及國家(伊斯蘭文明)間的對抗，而使得「文明衝突」論中所揭櫫的美國全球戰略更具現實性；尤其是，美國藉由全球反恐怖聯盟及攻打阿富汗，而讓美國有充裕的戰略空間因應中、俄漸趨密切的戰略合作關係，以及取得進入中、南亞地緣政治發展的絕佳機會。

　　　　　"The Clash of Civilizations" proposed by Huntington in 1993 became the center of extensive discussions again after the Sept. II terrorist attacks on America in 2001. This makes clear that Huntington has been an influential tactician on U.S. foreign policy and strategy design for a long time. "The Clash of Civilizations" helps the U.S. to seek new potential adversaries, consolidate the Western united front, and reconstruct her global strategy after the end of Cold War. The Spet. IIth attacks strongly highlighted the antagonisms between the U.S. (the Western civilization) and Islamic extremists/countries (the Islamic civilization). In particular, the global counter-terrorism coalition and war on Afghanistan allows the U.S. more space to cope with the China-Russia strategic cooperation, and offers an opportunity for the U.S. to interfere in geopolitical development in Middle/South Asia.