How long will America remain as the world's greatest power?

[tallguy23]

China is estimated to surpass the U.S. as the world's largest economy. How long will America remain as the world's greatest power? (economically, militarily, culture, etc. )

[dead0man]

A lot longer than the America haters want

[Frodo]

Depends, but potentially centuries to come.

China may become the world's largest economy within a decade, but the sheer scale of its domestic problems will ensure it will remain inward-looking for the foreseeable future.  And who knows?  Perhaps by the time it will have sorted itself out domestically, it may have become a mature parliamentary democracy -and a key ally of the United States.  

[DC Al Fine]

Taking a complete guess... another century or so.

[politicus]

Unlike other great empires in history the multiethnic character of US society and the large contingent territory makes it possible to compete with other great powers in terms of population (and thereby economy)  forever (the present US territory could sustain a population of 1 billion+). So it depends on whether America 1) wants to keep increasing its population and 2) can (re)create efficient political decision mechanisms and 3)force/convince the  wealthiest Americans to pay the taxes necessary to sustain military dominance. A fourth factor is breaking the curse of anti-intelectualism and investing heavily in the education of ordinary Americans to use more of your intelligence reserve.

I see no credible challenge to the soft, cultural power of the US will remain ahead in this area.

The inefficiency of the challengers is also to your advantage. Both China and India are facing enormous internal problems, so it will take a very long time to catch up. India may never get to be a superpower, despite its huge potential. China will experience some backlashes along the way.

[Blue3]

China is going to be facing huge problems in the coming decades, especially its demographic crisis. No other power will surpass America for decades and decades to come. Unless the Europeans form a unified state, a strong unified military, and a backbone against Russia, which all seem highly unlikely right now.

[Hamster]

There are no great powers.