This quotation comes from Fareed Zakaria's book The Post-American World: And the Rise of the Rest, and it expresses a fundamental tenet of Zakaria's thesis. Following the end of the Cold War and the demise of the Soviet empire, America has spent decades as the single world superpower. Now, however, this status begins to be challenged. Zakaria is not suggesting that the United States will suddenly collapse or that a single rival will emerge to replace the Soviet Union in opposition. What he does predict is "a slow shift in the nature of international affairs" away from unipolar American power.
To assess this quotation, is may be helpful to break it down into a number of simple assertions:
- America is still the dominant world power.
- This unipolar dominance will eventually end.
- There is no single rival to American power on a global scale.
- The various potential rivals to American power place constraints on the freedom of the US government to act in the world.
It is important to note that within this quotation, Zakaria does not say whether he thinks this state of affairs is good or bad, so there is no need to make such a value judgment in assessing his thesis.
It is difficult to argue with the first two points. The third is somewhat controversial, since many commentators view China as the single rival that will eclipse America. One of the most persuasive proponents of this viewpoint has been Martin Jaques, whose website is linked below. The fourth point is also open to challenge, though it is notable that America has been less active on the world stage since the wars in Iraq and Afghanistan. At least from a military point of view, it appears that America is not attempting to control world politics to the extent that it did in previous decades, and it may not be capable of doing so.