Far from Ukraine and Gaza, as the Group of 7 wealthy democracies gathers in Italy to discuss a range of old, entrenched challenges, the nature of American power is being transformed across the region that Washington sees as crucial for the century to come: the Asia-Pacific.

Here, America no longer presents itself as the confident guarantor of security, a trust-us-we’ve-got-this superpower. The terrain is too vast, China’s rise too great a threat. So the United States has been offering to be something else — an eager teammate for military modernization and tech development.

“In the past, our experts would talk about a hub-and-spokes model for Indo-Pacific security,” Defense Secretary Lloyd J. Austin III said this month at a global defense conference in Singapore. “Today we’re seeing something quite different.”

In this new era, many countries are doing more, on their own and with U.S. help. For the first time, the United States is building nuclear-propelled submarines with Australia; involving South Korea in nuclear weapons planning; producing fighter jet engines with India; sharing maritime surveillance duties with small Pacific islands; and working with Japan on adding an offensive strike capability.

Behind the scenes, U.S. officials are also testing new secure communications systems with their partners. They’re signing deals to co-produce artillery with allies and to secure blood supplies from hospitals around the region in case of a conflict. They are also training with many more nations in more expansive ways.

These collaborations highlight how the region sees China. Many countries fear Beijing’s growing military strength and belligerence — its threats against the democratic island of Taiwan, its claim to most of the South China Sea and its land grab at the border with India. They are also less sure about China as an economic partner, with the slowing pace of its post-Covid economy and tilt away from pro-growth, pro-entrepreneur policies under Xi Jinping.

But are the countries linking arms with the United States making a long-term bet on America over China? Or are they recognizing their own rising strength and behaving like pragmatists, getting what they can from a fitful superpower where an increasing number of voters want the country to stay out of world affairs?

In interviews with more than 100 current and former officials from the United States and countries across the Indo-Pacific over the past year, many said that the next century was likely to be less dominated by America than the last. No matter who wins the next election or the one after that, they said, the nation responsible for today’s world order has been weakened by the Iraq and Afghanistan wars, the destabilizing effects of China’s rise on domestic manufacturing and America’s own internal divisions.

The world is changing, too, with more nations strong enough to shape events. And as the United States shares sensitive technology and prioritizes teamwork, many believe they are witnessing both a global reshuffling and an evolution in American power.

For now, they argue, the United States is adapting to a more multipolar world. It is learning to cooperate in ways that many Washington politicians, fixated on American supremacy, do not discuss — with an admission of greater need and more humility.

America Diminished

The United States does not tower over the world like it used to.

Since World War II, the U.S. share of the global economy has been cut in half. That is mostly because of Asia’s steady economic rise. China alone produces around 35 percent of the world’s manufactured goods, three times the share of the United States. Japan, India and South Korea have also joined the top seven in terms of output, giving Asia more industrial heft than any other part of the world.

America’s military superiority has been better maintained, but China, with a smaller budget and sharper focus on the Indo-Pacific, now has a larger navy by number of ships, a likely lead in hypersonic weapons and many more factories to expand military production if needed.

American democracy is also not what it once was, as measured merely by the declining number of bills that presidents have signed into law. The Republican Party has repeatedly held up budgets, drawing the president back from trips overseas, in addition to delaying aid for partners like Ukraine and Taiwan. Recent polls show that most Republicans want the United States to take a less active role in solving the world’s problems.

Yet both parties have struggled with how to tackle and talk about Asia’s shifting power dynamics and America’s limits.

“It goes back several administrations,” said James L. Jones, a retired Marine Corps general who served as national security adviser under President Barack Obama. “We’ve had a fairly long period of time where the United States has sent conflicting messages.”

The Obama administration promised a “pivot to Asia” that seemed to never come. The Trump administration’s foreign policy — with its mix of anti-China diatribes and abandonment of a major trans-Pacific free-trade deal — was seen by some countries as a sign of U.S. insecurity about the challenge from Beijing.

China had already become an economic colossus, the most important trade partner for most nations in the Indo-Pacific, and a major investor.

Countries across the region have also spent the past few decades producing millions of new middle-class consumers and expanding sophisticated industrial production, fueling a surge of regional trade that made the U.S. market less important while allowing more Asian nations to build tighter bonds.

Both confidence and anxiety have emerged from these broader trends. Military budgets across Asia have soared in recent years, and the demand for American defense technology has never been higher.

Yet many countries in the region now see themselves as players in an emerging multipolar order. “We are the main characters in our collective story,” President Ferdinand R. Marcos Jr. of the Philippines said during a keynote speech at the conference in Singapore. And as a result, they have turned to the United States less as a protector than a provider of goods (weapons), services (training) and investment (in new technology and equipment maintenance).

Japan has made the sharpest turn. From easing tensions with South Korea to pulling back from decades of pacifism with plans to sharply increase its military budget, to signing troop movement agreements with Australia and other countries, Tokyo has made clear that it now seeks a leading role in protecting regional stability. But even as Washington welcomes the move, Tokyo’s actions grow in part from a critical assessment of the United States.

During a joint exercise with the American Air Force in Guam last year, Japanese commanders said they were expecting to become more active because Japan’s neighbors wanted Japan to do more, implying broad recognition that America’s future role was uncertain.

“The United States is no more what it used to be 20 years ago, 30 years ago,” said a senior Japanese intelligence official, who spoke on a condition of anonymity to avoid offending his American counterparts. “That’s the fact of the matter.”

“No matter who the next president is,” he added, “the role of the United States will be relatively diminished.”

America Adjusting

American officials are aware of the world’s doubts. When told that some counterparts in Asia saw humility in the American response, a handful of Washington officials winced, as if lemon juice had been squeezed into their eyes. It sounded too much like weakness.

But some Pentagon leaders have been open about seeking what analysts describe as “co-everything” with partners — co-development, co-production, co-sustainment. And while U.S. officials have talked for decades about alliances in Asia, their tone and actions over the past few years point to a subtle shift, toward a more decentralized approach to security and greater candor about their concerns.

Secretary of State Antony J. Blinken delivered a speech in September that called for greater humility in foreign policy to face “challenges that no one country can address alone.”

Gen. David H. Berger, the Marine Corps’ top general until he retired last year, launched a sweeping plan in 2019 to counter China’s strengths by redistributing American forces in Asia, shifting to smaller units that are now more mobile, with access to bases in many countries.

In Singapore, a senior defense official said the formula involves more capable nations, investing in themselves, in partnerships across the region, and in working with the United States, which now accepts that it need not be at the center of every relationship.

Hints of that humbler America can be seen in large, multinational military exercises, where other countries are playing bigger roles, and in smaller projects, such as a Pacific Fusion Center that opened last year in the Pacific island nation of Vanuatu. A data hub for maritime analysis of threats ranging from illegal fishing to Chinese encroachment, it had been conceived as a purely U.S. operation until local partners demanded a role and American officials backed down and brought them in.

India offers a more layered portrait of America’s evolution, pointing to sustained U.S. interest in long-term, comprehensive plans for working closely with an increasingly confident New Delhi — even if that means quieting down concerns about its democratic backsliding.

In interviews, some Indian officials said that a turning point arrived when the Americans pulled out troops from Afghanistan in August 2021, leaving behind scenes of stunning chaos that suggested more input from the region would have been useful.

“The U.S. did very little consultation in the run-up to withdrawal, and started doing much more after that,” one senior Indian diplomat said.

In meetings at the United States Embassy in India’s capital, against a backdrop of congressional hearings on the Jan. 6 attack on the Capitol, American officials softened and talked more about shared shades of gray in their democracies. Diplomats from both countries said concerns about the Indian government’s promotion of Hindu nationalism or suppression of dissent were sanded down to: “We have a lot of commonalities — extremism, hate speech, disinformation. How are you dealing with it?”

Along with a change in how American officials talked about their own country came a broadening of how they saw India: not just as a huge market, with the world’s largest population, but also a multiplier for innovation.

India graduates more than 1.4 million engineers each year, on par with China. At a time when the United States has become worried about Chinese advances in electric vehicles, missiles, quantum computing and other technologies, India could offer a pool of talent to help keep up.

It all came together in a strategic defense and technology-focused agreement unveiled during Prime Minister Narendra Modi’s state visit to Washington in 2023.

New Delhi was most excited about the co-production of fighter jet engines, which it had been seeking for years. But the White House emphasized in its own announcement that with shared investment in everything from nuclear energy to microchips, “no corner of human enterprise is untouched” by a partnership that spans “the seas to the stars.”

Pushed by other countries, the United States may finally be learning that a humbler approach can yield powerful results, said Ryan Crocker, a retired diplomat who served as U.S. ambassador to Afghanistan, Iraq, Pakistan, Syria, Kuwait and Lebanon.

“A certain degree of humility does not mean weakness,” he said. “We can’t do it all, we shouldn’t do it all. We have these relations and alliances, let’s figure out who does what.”

The Risks of American Actions

In conversations about America with defense leaders from the Philippines, Japan, India, Australia and other countries, there is often a hint of happy customers reviewing a bazaar.

The United States under President Biden has been selling and giving out quite a lot. Tomahawk missiles for Japan. Coast Guard boats for Vietnam. Improved runways for the strategically located island nation of Palau. Training for seemingly everyone in Asia who asks.

Is there danger in all that generosity?

Some analysts fear that America’s effort to spread its wares across a more fragmented world adds to the sensitive touch points for brinkmanship with China, raising the risk of a misunderstanding that could become a conflict.

“Washington’s pursuit of an increasingly complex lattice of security ties is a dangerous game,” wrote Mike M. Mochizuki and Michael D. Swaine, two defense researchers in Washington, in a recent essay for The New York Times.

At the Singapore conference in early June, China’s defense minister, Dong Jun, railed against what he described as “exclusive military alliances” that he said “cannot make our region safer.”

But if one risk of America’s collective approach involves doing too much, possibly sparking a confrontation, another could involve the U.S. failing to lock in enough from its partners.

There is a lot of ambiguity in the coalitions that increasingly define American power in Asia. How would the region respond if the Philippines stumbled toward a violent clash in the South China Sea? Or in a war over Taiwan — a center of the global chip business that China sees as its own lost territory — would the countries co-developing military equipment with the United States, or welcoming longer runways, actually spring into action?

It is also not clear how Washington itself would respond to Chinese aggression. And that uncertainty, according to many, is what countries are desperate to understand as they pull America closer.

“In the over 40 years I’ve known the United States, I’ve seen you go through troughs of being overly self-critical and waves of hubris,” said Bilahari Kausikan, one of Singapore’s most experienced diplomats. “One should not make the mistake of believing either is a permanent condition.”

The challenge for Asia and the world, he added, is that America is increasingly dysfunctional and “still indispensable”: No other country does as much to protect the order that other nations and economies need.

What’s changed is that a growing number of U.S. officials now acknowledge that more assistance is needed, from more than just familiar allies. In a time of disorienting challenges — Gaza, Ukraine, China, North Korea, pandemics, climate change, artificial intelligence, nuclear weapons — their jobs now involve convincing others that humility can be as American as confidence and that it’s built into a strategy that will last, no matter who is president.

When Adm. John Aquilino, in his final days as the head of the U.S. Indo-Pacific Command, was asked what his typical day looked like during an event in Australia in April, he didn’t mention aircraft carriers, just allies.

“I spend a lot of time either on the phone, on email or on an airplane out to visit my partners,” he said.

Many of his counterparts in the region, he added, have each other’s numbers on speed dial.