From his conclusion:
"History does not offer nations permanent security, and when it seems to offer hegemonic domination this usually is only to take it away again, often in unpleasant ways. The United States was fortunate to enjoy relative isolation for as long as it did. The conviction of Americans in the eighteenth and nineteenth centuries that the country was exempt from the common fate has been succeeded in the twenty-first century by an American determination to fight (to "victory," as the President insists) against the conditions of existence history now actually does offer. It sets against them the consoling illusion that power will always prevail, despite the evidence that this is not true.
"Schumpeter remarked in 1919 that imperialism necessarily carries the implication of
an aggressiveness, the true reasons for which do not lie in the aims which are temporarily being pursued...an aggressiveness for its own sake, as reflected in such terms as "hegemony," "world dominion," and so forth...expansion for the sake of expanding....
"This determination," he continues,
cannot be explained by any of the pretexts that bring it into action, by any of the aims for which it seems to be struggling at the time.... Such expansion is in a sense its own "object."
"Perhaps this has come to apply in the American case, and we have gone beyond the belief in national exception to make an ideology of progress and universal leadership into our moral justification for a policy of simple power expansion. In that case we have entered into a logic of history that in the past has invariably ended in tragedy."