Reporting from Washington -- First in a series of occasional reports on President Bush's legacy.

As President Bush's term comes to a close, the United States has the world's largest economy and its most powerful military. Yet its global influence is in decline.

The United States emerged from the Cold War a solitary superpower whose political and economic leverage often enabled it to impose its will on others. Now, America usually needs to build alliances -- and often finds that other powers aren't willing to go along.

In the 1990s, America exerted leadership in all the remote corners of the globe, from the southern cone of South America to Central Asia. Now, the United States has largely left the field in many regions, leaving others to step forward.

Bush has been blamed widely for the erosion of American prestige. And the decline in U.S. influence is partly the result of the reaction to his invasion of Iraq, his campaign against Islamic militants and his early disdain for treaties and international bodies.

But the shift is also a result of independent forces, though hastened by an aversion to Bush. These include the steady ascent of China, India and other developing countries that throughout the last decade have seen their economies grow, amassing wealth and quietly extending their reach.

As smaller countries have built economic and political ties to these rising powers, they have worked to free themselves from exclusive dependence on the United States.

"There is no return to the time when the United States was the 'indispensable power,' " said Stewart M. Patrick, a former State Department official at the Council on Foreign Relations. "The world has moved on."

Now there are multiple power centers. The institutions that buttressed Western power, such as the United Nations, the World Bank and International Monetary Fund, are under pressure to allow rising powers more influence.

A vivid illustration of the power shift came Nov. 15, when Bush convened world leaders in Washington to develop plans for dealing with the global economic crisis. In the old days, experts said, he would have limited the meeting to a few industrial powers. But Bush realized that the world economy now has a larger cast of influential players, and invited all members of the so-called Group of 20 developed and developing nations, which includes countries such as Argentina, Indonesia, Mexico and Turkey.

A decade ago, the U.S. might have been able to bring enough economic pressure on its own to force an end to Iran's disputed nuclear program, said Nikolas K. Gvosdev, professor of national security studies at the Naval War College.

But Iran has built economic ties to China and India, among others, so the United States has to assemble a much larger group if it hopes to force Tehran's hand.

"Ten years ago, the U.S. was generally the only game in town, and it had the power to close or crack open the door to Iran," Gvosdev said. "Now other countries have more options. . . . This doesn't mean the United States is weak, but it can't unilaterally impose what it wants."

The U.S. National Intelligence Council issued a report this year, "Global Trends 2025," that notes a shift of economic power from the West to the East that is "without precedent." In 2025, the United States will "remain the single most powerful country, but will be less dominant," it predicts.

Since World War II, the United States has led by its power of persuasion, as well as its economic might. But other countries' unhappiness with the Iraq war and the conduct of the Bush administration's "global war on terror," means that the "American brand is less legitimate and its persuasive powers are compromised," said Charles Kupchan of Georgetown University and the Council on Foreign Relations.

There also has been a dwindling of U.S. influence as the administration has focused most of its energy and resources on the Middle East and Southwest Asia, leaving much less for Central and Southeast Asia, Latin America and other regions. Many are going their own way, developing new ties among neighbors.

Latin American countries, for example, are building an organization called the Union of South American Nations and a NATO-like defense alliance called the South American Defense Council. The United States, long dominant in the hemisphere, is pointedly excluded from both.

An 8-year-old group called the Shanghai Cooperation Organization, with Russia, China, and four Central Asian states, has been slowly developing, in part because some members want a bulwark against U.S. involvement in the region.

Other countries are leading diplomatic initiatives that once would have been the province of the United States.

Qatar has taken the lead in brokering a deal between Syria and Lebanon, and Turkey has been acting as an intermediary between Israel and Syria.

As the United States' political standing has eroded, its economy has remained powerful. Its gross domestic product of $14 trillion a year dwarfs China's $7 trillion, adjusted for purchasing power.

Yet American influence on world economic policy is declining, too. One sign: the failure of the United States and its allies to sell a new agreement to the World Trade Organization in the face of opposition from China, India and other nations.

"The influence of the U.S. private sector is as strong as ever," said Gary C. Hufbauer of the Peterson Institute for International Economics. "But the United States is much less able to shape world policy these days."

Many analysts expect that the economic crisis, for which the U.S. is blamed by much of the world, will convince many countries that they shouldn't emulate the loosely regulated American economic model.

Another development is the weakening of U.S. ties with Europe. Once, when they formed a common front on an issue, they had enormous leverage.

The rift over the Iraq war has largely healed, but Europe continued to differ with the Bush administration on important issues, including climate change and Russia's resurgence.

Many analysts predict growing frictions over the joint effort in Afghanistan.

"There's a rebalancing of power away from the West," Kupchan said, "but also within the West."