Given a long enough timeline you can count on anyone to do the right thing. It's the balance of right to wrong which is more interesting. By this measure I don't think Americans are particularly exceptional.

Also, whether people choose to do the right thing is less interesting if they have no choice.

The quote means let americans fail because they'll get there eventually. After they've stubbornly tried everything else.

American's believe we're exceptional and dont have to learn from others. We'll do it OUR WAY and it'll work. We'll force it if we have to. This isn't something most people are consciously aware of, but it's something you can notice if you start to look for.