After the disruption of Soviet Union in 1990, America has become the only superpower in the world, which comes into post-cold era in later decade. Many scholars propose different kinds of contention toward America's foreign policy and effect her role in the world stage including the concepts of ”benign hegemony”, ”hegemony on the cheep”, ”preeminent, not dominant”. The writer of this article propose a series of comments on America's foreign policy by illustrating and analyzing cases in the past and makes a conclusion that America will be isolated if she continues pursuing hegemony interminably.