THE UNITED States has been the dominant world power since 1945, and U.S. leaders have long sought to preserve that privileged position. They understood, as did most Americans, that primacy brought important benefits. It made other states less likely to threaten America or its vital interests directly. By dampening great-power competition and giving Washington the capacity to shape regional balances of power, primacy contributed to a more tranquil international environment. That tranquility fostered global prosperity; investors and traders operate with greater confidence when there is less danger of war. Primacy also gave the United States the ability to work for positive ends: promoting human rights and slowing the spread of weapons of mass destruction. It may be lonely at the top, but Americans have found the view compelling.

When a state stands alone at the pinnacle of power, however, there is nowhere to go but down. And so Americans have repeatedly worried about the possibility of decline—even when the prospect was remote. Back in 1950, National Security Council Report 68 warned that Soviet acquisition of atomic weapons heralded an irreversible shift in geopolitical momentum in Moscow’s favor. A few years later, Sputnik’s launch led many to fear that Soviet premier Nikita S. Khrushchev’s pledge to “bury” Western capitalism might just come true. President John F. Kennedy reportedly believed the USSR would eventually be wealthier than the United States, and Richard Nixon famously opined that America was becoming a “pitiful, helpless giant.” Over the next decade or so, defeat in Indochina and persistent economic problems led prominent academics to produce books with titles like America as an Ordinary Country and After Hegemony.¹ Far-fetched concerns about Soviet dominance helped propel Ronald Reagan to the presidency and were used to justify a major military buildup in the early 1980s. The fear of imminent decline, it seems, has been with us ever since the United States reached the zenith of global power.

Debates about decline took on new life with the publication of Paul Kennedy’s best-selling Rise and Fall of the Great Powers, which famously argued that America was in danger of “imperial overstretch.” Kennedy believed Great Britain returned to the unseemly ranks of mediocrity because it spent too much money defending far-flung interests and fighting costly wars, and he warned that the United States was headed down a similar path. Joseph Nye challenged Kennedy’s pessimism in Bound to Lead: The Changing Nature of American Power, which sold fewer copies but offered a more accurate near-term forecast. Nye emphasized America’s unusual strengths, arguing it was destined to be the leading world power for many years to come.

Since then, a host of books and articles—from Charles Krauthammer’s “The Unipolar Moment,” G. John Ikenberry’s Liberal Leviathan and Niall Ferguson’s Colossus to Fareed Zakaria’s The Post-American World (to name but a few)—have debated how long American dominance could possibly last. Even Osama bin Laden eventually got in on the act, proclaiming the wars in Iraq and Afghanistan fatal blows to American power and a vindication of al-Qaeda’s campaign of terror.

Yet for all the ink that has been spilled on the durability of American primacy, the protagonists have mostly asked the wrong question. The issue has never been whether the United States was about to imitate Britain’s fall from the ranks of the great powers or suffer some other form of catastrophic decline. The real question was always whether what one might term the “American Era”was nearing its end. Specifically, might the United States remain the strongest global power but be unable to exercise the same influence it once enjoyed? If that is the case—and I believe it is—then Washington must devise a grand strategy that acknowledges this new reality but still uses America’s enduring assets to advance the national interest.

THE AMERICAN Era began immediately after World War II. Europe may have been the center of international politics for over three centuries, but two destructive world wars decimated these great powers. The State Department’s Policy Planning Staff declared in 1947 that “preponderant power must be the object of U.S. policy,” and its willingness to openly acknowledge this goal speaks volumes about the imbalance of power in America’s favor. International-relations scholars commonly speak of this moment as a transition from a multipolar to a bipolar world, but Cold War bipolarity was decidedly lopsided from the start.

In 1945, for example, the U.S. economy produced roughly half of gross world product, and the United States was a major creditor nation with a positive trade balance. It had the world’s largest navy and air force, an industrial base second to none, sole possession of atomic weapons and a globe-circling array of military bases. By supporting decolonization and backing European reconstruction through the Marshall Plan, Washington also enjoyed considerable goodwill in most of the developed and developing world.

Most importantly, the United States was in a remarkably favorable geopolitical position. There were no other great powers in the Western Hemisphere, so Americans did not have to worry about foreign invasion. Our Soviet rival had a much smaller and less efficient economy. Its military might, concentrated on ground forces, never approached the global reach of U.S. power-projection capabilities. The other major power centers were all located on or near the Eurasian landmass—close to the Soviet Union and far from the United States—which made even former rivals like Germany and Japan eager for U.S. protection from the Russian bear. Thus, as the Cold War proceeded, the United States amassed a strong and loyal set of allies while the USSR led an alliance of comparatively weak and reluctant partners. In short, even before the Soviet Union collapsed, America’s overall position was about as favorable as any great power’s in modern history.

What did the United States do with these impressive advantages? In the decades after World War II, it created and led a political, security and economic order in virtually every part of the globe, except for the sphere that was directly controlled by the Soviet Union and its Communist clients. Not only did the United States bring most of the world into institutions that were largely made in America (the UN, the World Bank, the IMF, and the General Agreement on Tariffs and Trade), for decades it retained the dominant influence in these arrangements.

In Europe, the Marshall Plan revitalized local economies, covert U.S. intervention helped ensure that Communist parties did not gain power, and NATO secured the peace and deterred Soviet military pressure. The position of supreme allied commander was always reserved for a U.S. officer, and no significant European security initiative took place without American support and approval. (The main exception, which supports the general point, was the ill-fated Anglo-French-Israeli attack on Egypt during the Suez crisis of 1956, an adventure that collapsed in the face of strong U.S. opposition.) The United States built an equally durable security order in Asia through bilateral treaties with Japan, South Korea, Australia, New Zealand, the Philippines and several others, and it incorporated each of these countries into an increasingly liberal world economy. In the Middle East, Washington helped establish and defend Israel but also forged close security ties with Saudi Arabia, Jordan, the shah of Iran and several smaller Gulf states. America continued to exercise a position of hegemony in the Western Hemisphere, using various tools to oust leftist governments in Guatemala, the Dominican Republic, Chile and Nicaragua. In Africa, not seen as a vital arena, America did just enough to ensure that its modest interests there were protected.

To be sure, the United States did not exert total control over events in the various regional orders it created. It could not prevent the revolution in Cuba in 1959 or Iran in 1979, it failed to keep France from leaving NATO’s integrated military command structure in 1966, and it did not stop Israel, India, North Korea and Pakistan from acquiring nuclear weapons. But the United States retained enormous influence in each of these regions, especially on major issues.

Furthermore, although the U.S. position was sometimes challenged—the loss in Vietnam being the most obvious example—America’s overall standing was never in danger. The U.S. alliance system in Asia held firm despite defeat in Indochina, and during the 1970s, Beijing formed a tacit partnership with Washington. Moreover, China eventually abandoned Marxism-Leninism as a governing ideology, forswore world revolution and voluntarily entered the structure of institutions that the United States had previously created. Similarly, Tehran became an adversary once the clerical regime took over, but America’s overall position in the Middle East was not shaken. Oil continued to flow out of the Persian Gulf, Israel became increasingly secure and prosperous, and key Soviet allies like Egypt eventually abandoned Moscow and sided with the United States. Despite occasional setbacks, the essential features of the American Era remained firmly in place.

Needless to say, it is highly unusual for a country with only 5 percent of the world’s population to be able to organize favorable political, economic and security orders in almost every corner of the globe and to sustain them for decades. Yet that is in fact what the United States did from 1945 to 1990. And it did so while enjoying a half century of economic growth that was nearly unmatched in modern history.

Image: Pullquote: Instead of trying to be the “indispensable nation” nearly everywhere, the United States will need to figure out how to be the decisive power in the places that matter.Essay Types: Essay