As modernizing nations narrow the technical gap separating them from advanced ones, and as dangerous technologies slowly but inexorably spread, the security of the world will be at risk if there are no advances in the resolution of international disputes. If this danger is to be reduced, Americans will need to begin to debate their future security in a longer-term way.
Americans are accustomed to seeing their security in terms of two extremes, the short-term and the indefinite long-term. Planning of U.S. foreign and defense policy extends to intervals of four years, which accord with the terms of presidential administrations and quadrennial defense reviews. The time beyond is indefinite or open-ended. This way of looking at the world has its roots not just in how the federal government is required to work but also in American assumptions about the world.
During the Cold War (1947-1989), Americans thought of their security in terms of commitments that had to be sustained over an indefinite period of time. America continued to think this way after the events of 2001, when policy makers viewed the conflict with al-Qaida as an open-ended struggle that would take decades to resolve.
Forecasts of imminent American decline have been premature. But in a modernizing world, it is inevitable that a nation with five percent of the population will someday cease to dominate unless it can attract more of the world's people to itself as friends and allies or as member states in its own union. America's great challenge will be to preserve its way of life in such a world. It will be a departure for the United States to anticipate conditions that are not open-ended but that are still several decades from realization. The rest of the world is no more inclined to think this far ahead. But if no one does, the future will arrive and no one will be prepared for its consequences.
A possible outcome for America is to belong to a community of nation-states having shared purposes that embraces most of the world's people. In this community, member states would agree to differ on some matters but share responsibility in a more equal way than they do in international bodies today.
The sooner the United States and other countries agree on the desirability of such an outcome, the greater the likelihood that it will come about in a peaceful way. If this does not happen, then a multipolar world will evolve with all of the risks that attend such a world.
Before then, public opinion needs to be asked, not to endorse any particular outcome, but to debate global security on a longer yet not open-ended timescale, in anticipation of a world that could either be an arena of multipolar rivalry or a world in which equals cooperate. The challenge to U.S. foreign policy will be to propose this choice while there is time to make a gradual transition.