US Deficits and the Chinese Challenge.

Debt can become a real liability for a superpower. Recall what happened to postwar Britain.

[This info taken from WSJ and pasted here as I find it interesting.]

Consider what happened in 1946, when a cash-strapped Great Britain turned to the U.S. for a loan. For 30 years or more, the British had been consumed by the threat of a rising Germany. Two wars had been fought, millions of lives had been lost, and the British treasury was dramatically depleted in the process. Britain survived, but the costs were substantial.
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Unable to take no for answer, Britain explained that unless it received funds the government would be insolvent. The Americans came back with a series of conditions. They would lend Britain $3.7 billion at 2% interest, and the British government would have to abide by the 1944 Bretton Woods plan, which made the dollar rather than the pound sterling the reference point for global exchange rates and required Britain to make the pound freely convertible. Even more significantly, Britain had to end its system of imperial preferences, which meant no more tariffs and duties on goods to and from colonies such as India. These were not mere financial penalties: Taken together, they meant the end of the British Empire.

Within two years, Britain had left India and was on its way to decolonizing throughout Asia and Africa. Unable to compete with the United States economically and no longer able to reap the benefits of colonial trade, Britain's military shrank and its commerce contracted. It quickly receded from its dominant global position and entered several decades of economic malaise. In the 1980s, Britain finally emerged as a prosperous country, but it was a shadow of what it had been in its heyday.


Similarly, can it happen with Chinese with US?

More details -
http://online.wsj.com/article/SB10001424052748704107204574469073847604010.html