This is actually a heck of a compliment to the US. The reason for the EU was to unite enough European states to form an economy equal to the US. While we get bigger by growing more productive, the stagnate EU has to grow by adding new territory. This article, in so many words, says in twenty years they will need 650 million Europeans to compete with us.
Although I have serious doubts about their ability to be successful, I can't help but think of how the world will change if they are considering their animosity towards us.
Without size and wealth as an advantage, what happens? I don't like to think about it.