Only residents of the U.S. would be presumptious and preposterous enough (Can you spell "Hubris"?) to adopt the term "Americans" as pertaining solely to the residents of the United States- particularly as the only real "Americans"- the indigenous populations- were early on annihilated by their European Immigrant progenitors.

As to the psychological problems of U.S. citizens who takes offense at the term "colonials"- and who doubtless routinely refers to residents of the British Isles as "Brits" and residents of Scotland as "English", enough has been said above.

C'mon, folks....