This brings us to the Palestinian problem. The reason to address the Palestinian problem is not that it would put an end to Shi‘a and Sunnis killing each other in Iraq, make Bashir al-Asad an altruist in Lebanon, or persuade the mullahs in Tehran to abandon their nuclear ambitions. Rather, as every moderate Arab leader in the region has told the United States, the perceived American double-standard on the Israeli-Palestinian dispute makes it much more difficult for them to support U.S. positions or to do essential heavy lifting on America's behalf on other issues. It also makes it harder for Supreme Leader Khamenei and President Asad to accommodate American concerns in Iraq and elsewhere without losing face in their own countries.

The other side of the coin is putting intense pressure on Iran and Syria to demonstrate to them that the United States is indeed in a position to form a meaningful coalition against them with appropriate international legitimacy, including through United Nations Security Council resolutions. Already, leading European and Asian allies have indicated to Washington that without the cover of legitimacy the UN provides, they would be very reluctant to join any U.S. effort. That inevitably brings Russia and its veto into the picture.

Much is said, and sometimes with considerable justification, about Russia's departure from democracy at home and its propensity toward applying heavy-handed pressure to its new neighbors. But publicizing Russia's misdeeds, real and imagined alike, is not a substitute for achieving what is needed. The United States must either be prepared to bargain with a resurgent Moscow who cannot be intimidated or bribed as was done with Yeltsin's Russia during the 1990s, or be prepared to pay the much higher costs for taking action without Russian cooperation.

This is why realists have a different perspective on the question of NATO's further expansion east. For the crusaders of moralpolitik, the alliance is a near-mystical union of "democracies", and must be broadened to bring in all states that desire membership, even at the cost of ratcheting tensions up with other major powers.

But common sense suggests one other major criterion: does expansion of the alliance enhance its capabilities and ultimately U.S. security? Would, for instance, the number of troops potentially committed to NATO missions by states like Ukraine and Georgia compensate for turning Russia into America's adversary?

The idea that foreign policy decisions require hard-headed analysis and difficult choices is apparently offensive to those who believe that international affairs is a morality play and the United States is a global hegemon entitled, and indeed obliged, to right what they see as global wrongs. But being realistic about American options and dilemmas is not an obstacle to morality-on the contrary, it is an essential requirement in pursuing a high-minded policy that produces not only warm feelings in our hearts but results that matter and endure.

After the collapse of the Soviet Union, there was a period when the United States could act on the world stage without much opposition from other major states. Today, however, existing and emerging centers of power seem much less willing to delegate de facto world government to the United States-no matter who is in charge, whether Democrats or Republicans.

Both Russia and China today accept that they need the United States more than they need each other-and this is especially true given China's economic orientation. But if Moscow and Beijing believe that they are both being quietly encircled by the United States-either by NATO expansion further east or by some sort of global "democracy alliance", they may change their calculations. They already appear to be hedging their bets in the framework of the Shanghai Cooperation Organization. A Chinese-Russian axis would likely be tactical, taking into account their divergent interests and mutual distrust. But even temporary rapprochement could deliver a severe blow to U.S. global leadership. Throw in disaffected continental European powers and India, and a considerable dent could be placed in America's ability to isolate rogue states, put effective pressure on nuclear proliferators and deprive non-state terrorist organizations of their indispensable protectors. Witness Iran's faith in the "powers of the east" to circumvent any American-initiated economic sanctions and to provide some counter-balance to the United States.

Henry Kissinger has offered the wise observation that "so long as Iran views itself as a crusade rather than a nation, a common interest will not emerge from negotiations." But this observation is equally applicable to the United States. Many nations can embrace American world leadership, though obviously with different degrees of enthusiasm-if such leadership reinforces a global system based on free trade, secure lines of communication and a commitment to stability. Others might acquiesce more reluctantly-so long as they do not feel that America is engaged in a global crusade directed against them or at the expense of their vital interests.

The stakes could not be higher. In his ground-breaking new book, Annihilation from Within, Reagan Administration defense official and Washington wise-man Fred Iklé warns that "the dark side of progress"-revolutionary new technologies of human destruction, whether nuclear, biological or even in artificial intelligence-has exceeded the development of the international system and the states within it. Iklé is concerned that "Living comfortably on borrowed time, most democratic societies lack the will and foresight needed to defend against" the grave dangers that may come. September 11 may look trivial to what the United States and others may experience unless we focus on these apocalyptic threats, even at the occasional expense of desirable but optional pursuits. Moreover, notwithstanding "the appealing vision of a new ‘flat world'", he writes, today's globe is still dominated by states pursuing their individual interests. History will not judge kindly those who neglect a real and present danger to the survival of democracy in the United States and Europe in the name of promoting democracy on a global scale. And, Iklé makes a powerful case that the use of Weapons of Mass Destruction by non-state actors can create precisely such a disastrous outcome.

The bottom line is that notwithstanding often disingenuous references to the "international community", our dangerous world is still dominated by states and, yes, their governments. Under these circumstances, America cannot lead if it disregards the interests and priorities of others. Telling those others what we think their interests are does not work; sovereign nations like to make such decisions themselves. And when President George W. Bush is viewed as a greater threat to world peace than either Kim Jong-il or Mahmoud Ahmadinejad (less a threat than Osama bin Laden alone), in major international polls, few abroad are inclined to accept that Washington knows best. It is not cynical defeatism but patriotic desire to strengthen U.S. global leadership that should persuade us to end the crusade. Now.

Dimitri K. Simes is president of The Nixon Center and publisher of The National Interest.