US historian has ominous predictions for the future of America

Alfred McCoy is a professor of history at the University of Wisconsin at Madison. He thinks the American empire has passed the point of no return and is now in a death spiral:

A soft landing for America 40 years from now? Don’t bet on it. The demise of the United States as the global superpower could come far more quickly than anyone imagines. If Washington is dreaming of 2040 or 2050 as the end of the American Century, a more realistic assessment of domestic and global trends suggests that in 2025, just 15 years from now, it could all be over except for the shouting.

Despite the aura of omnipotence most empires project, a look at their history should remind us that they are fragile organisms. So delicate is their ecology of power that, when things start to go truly bad, empires regularly unravel with unholy speed: just a year for Portugal, two years for the Soviet Union, eight years for France, 11 years for the Ottomans, 17 years for Great Britain, and, in all likelihood, 22 years for the United States, counting from the crucial year 2003.

Future historians are likely to identify the Bush administration’s rash invasion of Iraq in that year as the start of America's downfall. However, instead of the bloodshed that marked the end of so many past empires, with cities burning and civilians slaughtered, this 21st-century imperial collapse could come relatively quietly through the invisible tendrils of economic collapse or cyberwarfare.

But have no doubt: When Washington's global dominion finally ends, there will be painful daily reminders of what such a loss of power means for Americans in every walk of life. As a half-dozen European nations have discovered, imperial decline tends to have a remarkably demoralizing impact on a society, regularly bringing at least a generation of economic privation. As the economy cools, political temperatures rise, often sparking serious domestic unrest.

From the Huffington Post. The reasons are ones that should be familiar by now; he expects that the US dollar will eventually lose its reserve status, the country has badly overextended itself with its foreign military adventures, and its economy is gradually being hollowed out as manufacturing increasingly moves offshore. While his predictions are fairly good as they go, I'm not sure I agree with his assumption that China will simply replace the US as the world's most powerful country. The biggest issue is not mentioned in the article -- namely, climate change -- and this will harm China at least as much as the US.