Thus, in terms of legitimacy, balance of power, and international institutions, the United States is quite a lot weaker than it once was. It does not have the obvious option to exercise military power against Iran if it continues to pursue a nuclear weapons program, and it is hard to see how the United States can deal with North Korea if it continues to defy the international community.

To what extent do you believe that China will replace the United States as the next dominant power in the world?

China has an awful long way to go. If you project forward even to 2050, the average American will still be 3 times richer than the average Chinese, and that is assuming everything goes well in China. China is not all Shanghai, and one should not be deluded into thinking that it is by a single visit to the “great center of economic growth.” I think the United States is streets ahead of China in terms of technology and also, of course, in more general economic terms.

Those who predict a very rapid Chinese ascent are probably overdoing it. China has to negotiate some extremely dangerous waters as its process of urbanization continues. It is growing at great speed, with enormous social stresses and strains, to say nothing of environmental problems. I personally would be very surprised if China passes through this period of its history without at least one major financial crisis. And who knows what the political consequences of a big Chinese financial crisis would be?

From an economic point of view the United States is still second to none, despite the size of its current account deficit. From the point of view of social cohesion, it is extraordinarily strong internally, despite differences between the political parties. The United States is currently one of the most stable societies in the world. The rebalancing of the world from the West to the East is going to be a very gradual, protracted process, and I do not think one should expect that in 10, 20, or even 30 years, we will look around us and say, “This is the Chinese century.”

Looking ahead to 20 years from now, what do you expect the power structure of the world to look like? Will an imperial order exist, and are you optimistic about this structure?

We are entering a world with multiple empires: empires of energy in the cases of Russia and Iran, energy-importing empires in the case of China and the United States, and the strange phenomenon of the European Union, which is a pseudo-empire since it is large but militarily impotent. Therefore, there is a kind of return to multipolarity, but not just multipolarity. We are not simply replaying the Cold War with more than two players, which is essentially what multipolarity implies. The current situation of power in the international arena is much more like a return to the pre-1914 world of multiple empires that are not necessarily able to harmonize their interests.

I am far from optimistic about this multipolar world of the future. The potential for civil war in Iraq to escalate into a major regional conflict is very real, and the difficulties of containing it through international institutions are becoming increasingly obvious. The world today is much more dangerous than the world of 1914 because today, both rogue regimes and terrorists have nuclear weapons. Back in 1914, terrorists only had hand grenades and pistols. Moreover, the United States is less able to meet these dangers than it was—largely because its credibility has taken a tremendous hit by its failure to stabilize Iraq.