Well, there is a psychological difference, Ebbie, but you'd have to grow up in both countries to notice it, I think. I did. I spent half my childhood in Canada, half in the USA.

Young Americans are brought up with certain assumptions woven indelibly into the culture all around them, and it affects their viewpoint. Assumptions such as: "We are the country that invented democracy (and freedom)." "We are the greatest country in the world." "Life is better here than it is anywhere else." "We have a mission to lead the world to a better way." "Our money is the most important currency in the world." Etc...it's a very ethnocentric, self-absorbed point of view.

Those assumptions are radically different from the more modest assumptions of people in countries which are not superpowers. They are the kind of assumptions which can be very badly used by unscrupulous political leaders, and the USA is not the only country which has gone down that particular path. The Romans did. The British did. The French did. The Germans did. The Russians did.   The Japanese did.

All in their own time. Eventually their time passed...for some sooner than for others.

People in smaller countries observe that kind of hubris with nervousness and resentment, and sometimes they have good reason to be nervous.