When historians try to understand the world of the early 21st century, they should take note of the Parsley crisis. In 2002, the government of Morocco sent 12 soldiers to a tiny island called Leila in the Straits of Gibraltar and planted its flag there.

The island is uninhabited and all that thrives on it is wild parsley, hence its Spanish name, Perejil. But its sovereignty had long been contested and the Spanish government reacted forcefully: 75 Spanish soldiers were airlifted onto the island; they pulled down the Moroccan flag, hoisted two Spanish flags and sent the Moroccans home. The Moroccan government denounced the “act of war” and Spain put its warships off the coast of Morocco.

From afar the whole affair looked like a comic opera. But someone was going to have to talk the two countries down. That role fell not to the United Nations, or to the European Union, or to France, which has good relations with both sides. It fell to the United States. “I kept thinking to myself, ‘What do I have to do with any of this?’ ” recalled Colin Powell, who was secretary of state.

Once it became clear that nothing else was working, he began a hectic round of telephone diplomacy from home on a Friday night: “I decided that I had to push for a compromise fast because otherwise pride takes over, positions harden and people get stubborn. And my grandkids were going to come over soon for a swim.”

By Saturday morning he had drafted an agreement on his home computer. He got both sides to accept it, signed for each side himself and faxed it to Spain and Morocco. They issued statements thanking the United States for helping to resolve the crisis. Powell got to go swimming with his grandkids.

It is a small example but a telling one. The United States has no interests in the Strait of Gibraltar. But it was the only country that could resolve the dispute for a simple fundamental reason. In the unipolar world we have lived in since the collapse of the Soviet Union in 1991, it is the single superpower.

That summer of 2002 will be seen as the high water mark of unipolarity, America’s Roman moment. The decade leading up to it had been a heady time. The economy had been roaring, the dollar had been sky-high and American CEOs had been global super-stars. Then, after the attacks of 9/11, America had single-handedly put terrorism at the top of the global agenda. That was then.

America remains the global superpower today but an enfeebled one. At a military-political level it still dominates the world but the larger structure of unipolarity - economic, financial, cultural - is weakening.

Partly this is because of the “rise of the rest”. Russia, which in the 1990s was dependent on American aid and loans, now posts budget surpluses in the tens of billions of dollars. East Asian nations, which once desperately needed the International Monetary Fund to bail them out, now finance America’s debt. China, where economic growth was driven almost entirely by US demand in the 1990s, has surpassed America as the world’s largest consumer market in several key categories.

There is also another reason. The United States has had an extraordinary hand to play in global politics, the best of any country in history. Yet by almost any measure - problems solved, success achieved, institutions built, reputation enhanced - it has played this hand badly. How did America blow it? Beyond specific personalities and policies, about which much has been written, the condition that made such errors possible was, ironically, America’s immense power.

AMERICANS firmly believe in the virtues of competition. We believe that individuals, groups and corporations perform better when they are in a competitive environment. When it comes to the international arena, however, we have forgotten this.

Ever since the collapse of the Soviet Union, America has walked the world like a colossus, unrivalled and unchecked. This has had its benefits but it has also made Washington arrogant, careless and lazy.

We didn’t start out careless. When the Soviet Union was collapsing, President George H W Bush never acted like the head of the sole superpower. Rather than claiming victory in the cold war, his administration carefully consolidated the gains of Soviet collapse, always aware that the process could either reverse or end in violence.

American power became more apparent during the Clinton years. Foreign problems, no matter how distant, always seemed to end up in Washington’s lap. Other countries were often part of the solution but, unless America intervened, the crisis persisted - in the Balkans, in East Timor, in successive Middle East conflicts, in the east Asian economic crisis and Latin American debt defaults.

Washington became more assertive - and foreign governments more resistant. Some of Clinton’s people were accused of arrogance. But these complaints were polite chatter compared with the hostility aroused by George W Bush. He had a united country and a largely sympathetic world. But the Afghan war heightened the aura of US omnipotence, emboldening the most hard-line elements in the administration. America didn’t need the rest of the world or the old mechanisms of legitimacy and cooperation. It was the new global empire that would create a new reality - so the argument went.

It was not just the substance of American policy that changed in the unipolar era. So did the style, which has become imperial and imperious. There is much communication with foreign leaders but it’s a one-way street. Other governments are often simply informed of US policy. Senior American officials live in their own bubbles, rarely having genuine interaction with their overseas counterparts, let alone other foreigners. Bush’s foreign visits - he was in London last week - seem designed to require as little contact as possible with the countries he visits.

“When we meet American officials they talk and we listen - we rarely disagree or speak frankly because they simply can’t take it in. They simply repeat the American position, like the tourist who thinks he needs to speak louder and slower and then we will understand,” a senior foreign policy adviser in a European government told me. To foreigners, US officials seem clueless about the world they are supposed to be running.

“There are two sets of conversations, one with Americans in the room and one without,” says Kishore Mahbubani, formerly Singapore’s UN ambassador. Because Americans live in a “cocoon”, they don’t see the “sea change in attitudes towards America throughout the world”.

It is too easy to dismiss the hostility that grew out of Bush’s Iraq campaign as just envious antiAmericanism (even if some of it is). For most of the world the Iraq war was not about Iraq; it was about America. People worry about sharing a planet in which one country has so much power. Even if Iraq works out, the America problem will remain.

Nicolas Sarkozy is unabashedly pro-Amer-ican and makes clear that he wants to emulate the United States in many ways. When he met Condoleezza Rice, the US secretary of state, after his election as France’s president, she asked: “What can I do for you?”

His response was revealing. “Improve your image in the world,” he said. “It’s difficult when the country that is the most powerful, the most successful - that is, of necessity, the leader of our side - is one of the most unpopular countries in the world. It presents overwhelming problems for you and overwhelming problems for your allies. So do everything you can do to improve the way you’re perceived - that’s what you can do for me.”

Robert Kagan, the neoconservative writer, argues that America cannot be expected to act differently; it simply “behaves as powerful nations do”. But this argument misunderstands the unique place that America occupied in 20th-century diplomacy.

It was the most powerful country in the world when it proposed the creation of the League of Nations to manage international relations after the first world war. It was the dominant power at the end of the second world war when it founded the UN, created the Bretton Woods system of international economic cooperation and launched the world’s key international organisations.

America had the world at its feet in 1945 but presidents Franklin Delano Roosevelt and Harry Truman chose not to create an American imperium. Instead they built an international order of alliances and multilateral institutions and helped to get the rest of the world back on its feet by pumping out vast amounts of aid and private investment.

The United States built dams, funded magazines and provided technical know-how to other countries. It sent its scholars and students abroad so people got to know America and Americans. It showed deference to its allies, even when they were in no sense equals. It conducted joint military exercises with small nations that added little to US defence readiness. For half a century American presidents and secretaries of state circled the globe and hosted their counterparts in a never-ending cycle of diplomacy.

All these exertions produced a pro-Ameri-can world that was rich and secure. They laid the foundations for a booming global economy in which others could participate and in which America thrived. But it was an enlightened self-interest that took into account the interests of others. Above all, it reassured countries - through word and deed, style and substance - that America’s mammoth power was not to be feared.

THE task for today is to construct a new approach for a new era, one that responds to a global system in which power is far more diffuse than before and in which everyone feels empowered. The rise of the rest ensures America a vital, although different, role.

As China, India, Brazil, Russia, South Africa and a host of smaller countries all do well in the years ahead, new points of tension will emerge among them. Many of these countries have historical animosities, border disputes and contemporary quarrels with one another that give the United States an opportunity to play a large and constructive role as “honest broker” at the centre of the global order. It is a role that the United States - with its global interests and presence, complete portfolio of power and diverse immigrant communities - could learn to play with great skill.

This is quite different from the traditional superpower role. It is not a top-down hierarchy in which America makes decisions and then informs a grateful (or silent) world. It involves consultation, cooperation and even compromise - but, in a world with many players, setting the agenda and organising coalitions become primary forms of power.

There is still a strong market for American power. “No one in Asia wants to live in a Chinese-dominated world. There is no Chinese dream to which people aspire,” explained Simon Tay, a Singaporean scholar.

There also remains a strong ideological demand. Fernando Henrique Cardoso, a former president of Brazil, has argued that what the world really wants from America is that it affirm its own ideals.

That role, as the country that will define universal ideals, remains one that only America can play. Its soft power, in this sense, is intricately linked to its hard power. But it is the combination of the two that gives it a unique role in world affairs. Before it can implement any strategies for the new era, however, America must make a much broader adjustment. It needs to stop cowering in fear. It is fear that has created a climate of paranoia and panic in the United States and fear that has enabled our strategic missteps.

By almost all objective measures it is in a blessed position today. Compared with any of the massive threats of the past - Nazi Germany, Stalin’s aggression, nuclear war – the circumstances are favourable and the world is moving its way. Yet America has become a nation consumed by anxiety, worried about terrorists and rogue nations, Muslims and Mexicans, foreign companies and free trade, immigrants and international organisations.

The strongest nation in the history of the world now sees itself as besieged by forces beyond its control. Too many Americans have been taken in by a rhetoric of fear.

Having spooked ourselves into believing that we Americans have no option but to act fast and alone, preemptively and unilaterally, we have managed to destroy decades of international goodwill, alienate allies and embolden enemies, while solving few of the international problems we face. Through inattention, fear and bureaucratic cowardice, the caricature of the bad American threatens to become reality.

While some of foreign policy is what we do, some of it is also who we are. While American actions across the world have sometimes seemed harsh, misguided or unfair, America itself has always been open, welcoming and tolerant.

In the autumn of 1982 I arrived from India as a student of 18. America was in rough shape. Unemployment hit 10.8%, higher than at any point since the second world war. Interest rates hovered around 15%. Vietnam, Watergate, the energy crisis and the Iranian hostage crisis had all battered American confidence. The Soviet Union was on a roll, expanding its influence far beyond its borders, from Afghanistan to Angola and central America. Israel invaded Lebanon, making a volatile situation in the Middle East even more tense.

Yet America was a strikingly open and expansive country. President Ronald Reagan embodied it. Despite record low approval ratings, he exuded optimism from the centre of the storm. In the face of Moscow’s rising power he confidently spoke of a mortal crisis in the Soviet system and predicted that it would end up on “the ash heap of history”.

Everywhere I went the atmosphere was warm and welcoming. It was a feeling I had never had before. To a young visitor it seemed to offer generosity and promise.

For America to thrive in this new and challenging era, for it to succeed amid the rise of the rest, it needs to fulfil only one test. It should be a place that is as inviting and exciting to the young student who enters the country today as it was for this awkward 18-year-old a generation ago.

© Fareed Zakaria 2008

Extracted from The PostAmerican World by Fareed Zakaria, to be published by Penguin on July 3 at £20. Copies can be ordered for £18, including postage and packing, from The Sunday Times BooksFirst on 0870 165 8585

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