http://finance.yahoo.com/tech-ticke...-China?tickers=FXI,PGJ,^GSPC,^dji,SPY,LMT,RTN The U.S. is an empire in decline, according to Niall Ferguson, Harvard professor and author of The Ascent of Money. "People have predicted the end of America in the past and been wrong," Ferguson concedes. "But let's face it: If you're trying to borrow $9 trillion to save your financial system...and already half your public debt held by foreigners, it's not really the conduct of rising empires, is it?" Given its massive deficits and overseas military adventures, America today is similar to the Spanish Empire in the 17th century and Britain's in the 20th, he says. "Excessive debt is usually a predictor of subsequent trouble." Putting a finer point on it, Ferguson says America today is comparable to Britain circa 1900: a dominant empire underestimating the rise of a new power. In Britain's case back then it was Germany; in America's case today, it's China. "When China's economy is equal in size to that of the U.S., which could come as early as 2027...it means China becomes not only a major economic competitor - it's that already, it then becomes a diplomatic competitor and a military competitor," the history professor declares. The most obvious sign of this is China's major naval construction program, featuring next generation submarines and up to three aircraft carriers, Ferguson says. "There's no other way of interpreting this than as a challenge to the hegemony of the U.S. in the Asia-Pacific region." As to analysts like Stratfor's George Friedman, who downplay China's naval ambitions, Ferguson notes British experts - including Winston Churchill - were similarly complacent about Germany at the dawn of the 20th century. "I'm not predicting World War III but we have to recognize...China is becoming more assertive, a rival not a partner," he says, adding that China's navy doesn't have to be as large as America's to pose a problem. "They don't have to have an equally large navy, just big enough to pose a strategic threat [and] cause trouble" for the U.S. Navy.