I've been an out American for 7 years now, first two in Switzerland, the last 5 in China. I still think America has a lot going for it. Switzerland is efficient and fair, but something is missing because of restrained competition and protectionism. China is the exact opposite, and its hard to believe the system works at all. For whatever troubles America has, our system still works and is rather effective; no one is really coddled and you have to work hard, but social mobility is still better in the US than anywhere else.
There are people ignorant about the world in any country, I'm not sure why we always single out home bound Americans for being apathetic to world events. There is plenty of that to go around, even in Europe where people tend to travel more to other countries, but especially in China and even in Japan where people have many misconceptions about the rest of the world.
There are no more superpowers, not when IEDs are easy enough to procure by anyone.