Well, one possible perspective is that during a lot of the 20th century the US held itself to be morally superior to the "colonial" powers as they didn't have an empire.

However, the US - like Russia, didn't colonize other "nations" it appears to have mostly completely supplanted them in the areas it grew into.

Of course, this is only of historical interest, but as a wise man once wrote: "Who controls the past controls the future".