In
"The Paradox of American Power" by J. Nye which was published shortly after 9/11, the author predicted that really, nothing was holding the US back in terms of continued economic and cultural hegemony. Not China, not Europe, and certainly not the players in the middle east. By his reasoning "Soft Power" , ie popular culture, music, joint diplomacy and trade policies have as much or more influence than "Hard Power: ie military or unilateral economic measures.
Soft power brings respect and nations are more likely to respond in kind which results in real advances and of course has monetary benefits. There's a whole lot more to it in the book, which is a good read, albeit a bit dated (or prescient) right now.
They only thing he envisioned that could really derail the US was if we spent our time, money and debased our "soft power" fighting un-necessary wars or through other global
PR blunders.
Read it and draw your own conclusions.
http://www.amazon.com/Paradox-American-Power-Worlds-Superpower/dp/0195150880