Here's a Washington Post story quoted by Polipundit:

"I get the sense that even the most even-keeled observers are so disillusioned by Iraq, official sleaze, corporate greed, fiscal madness and so on that they fear the whole American enterprise is fundamentally diseased. Ask your friends which country will be most dominant in 50 years, and you’ll be unlikely to hear anyone say “the United States.”

…

'But if global power is measured by military might, no other country is within light years of America. Our military expenditures, according to Cullen Murphy, are about equal to the defense expenditures of the next 15 nations combined.

North Korea spends approximately $5 billion a year on its military. That is what the Pentagon leaves as a tip for a waiter. That’s what we spend on condiments! That’s our ketchup and mustard budget!

The gross domestic product of the United States for 2007 probably will be in the vicinity of $13.2 trillion. China is right around $2.6 trillion – in fourth place, after the United States, Japan and Germany.

China’s rivers are sewers. Environmental problems make the Chinese economic boom unsustainable. That’s the recent assessment of China’s deputy minister for the environment in an interview with the German magazine Der Spiegel: “This miracle will end soon because the environment can no longer keep pace. Acid rain is falling on one third of the Chinese territory, half of the water in our seven largest rivers is completely useless, while one fourth of our citizens does not have access to clean drinking water.”

Moreover, China will be the first country to get old before it gets rich. China’s one-child policy, so rigidly enforced in the 1980s and 1990s, will haunt the country as it finds itself without enough workers to support a geriatric population.

My colleague Joel Garreau recently surveyed global demographic trends for Smithsonian magazine and concluded that the United States is in far better shape than any potential rival. By 2020, there will be only one German worker for every German pensioner. Japan is rapidly aging and having few babies. Russia combines a low birthrate with decreasing life expectancy. Every year, 700,000 more Russians die than are born.'

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Americans are blessed with a durable Constitution, cultural diversity, abundant resources and an open society. I think we’re capable of solving our problems. That’s the position, too, of Murphy, whose America/Rome meditation ends on a hopeful note. He writes that a fundamental characteristic of Americans is the belief that improvement is possible. Sure, we’re making many of the mistakes the Romans made: “But the antidote is everywhere. The antidote is being American.”