In the case of the United States of America, the pioneering period did not consist of a barbarian conquest of an effete civilisation, Sir John Glubb notes, but of the conquest of barbarian peoples:
Thus, viewed from the outside, every example seems to be different. But viewed from the standpoint of the great nation, every example seems to be similar.
The United States arose suddenly as a new nation, and its period of pioneering was spent in the conquest of a vast continent, not an ancient empire. Yet the subsequent life history of the United States has followed the standard pattern which we shall attempt to trace — the periods of the pioneers, of commerce, of af?uence, of intellectualism and of decadence.