Another excellent essay by Krauthammer:
We are unlike Rome, unlike Britain and France and Spain and the other classical empires of modern times, in that we do not hunger for territory. The use of the word “empire” in the American context is ridiculous. It is absurd to apply the word to a people whose first instinct upon arriving on anyone’s soil is to demand an exit strategy. I can assure you that when the Romans went into Gaul and the British into India, they were not looking for exit strategies. They were looking for entry strategies.