When President Obama visits China for the first time on Sunday, he will, in many ways, be assuming the role of profligate spender coming to pay his respects to his banker.

That stark fact — China is the largest foreign lender to the United States — has changed the core of the relationship between the United States and the only country with a reasonable chance of challenging its status as the world’s sole superpower.

The result: unlike his immediate predecessors, who publicly pushed and prodded China to follow the Western model and become more open politically and economically, Mr. Obama will be spending less time exhorting Beijing and more time reassuring it.

In a July meeting, Chinese officials asked their American counterparts detailed questions about the health care legislation making its way through Congress. The president’s budget director, Peter R. Orszag, answered most of their questions. But the Chinese were not particularly interested in the public option or universal care for all Americans.

“They wanted to know, in painstaking detail, how the health care plan would affect the deficit,” one participant in the conversation recalled. Chinese officials expect that they will help finance whatever Congress and the White House settle on, mostly through buying Treasury debt, and like any banker, they wanted evidence that the United States had a plan to pay them back.

It is a long way from the days when President George W. Bush hectored China about currency manipulation, or when President Bill Clinton exhorted the Chinese to improve human rights.

Mr. Obama has struck a mollifying note with China. He pointedly singled out the emerging dynamic at play between the United States and China during a wide-ranging speech in Tokyo on Saturday that was meant to outline a new American relationship with Asia.

“The United States does not seek to contain China,” Mr. Obama said. “On the contrary, the rise of a strong, prosperous China can be a source of strength for the community of nations.”

He alluded to human rights but did not get specific. “We will not agree on every issue,” he said, “and the United States will never waver in speaking up for the fundamental values that we hold dear — and that includes respect for the religion and cultures of all people.”

White House officials have been working for months to make sure that Mr. Obama’s three-day visit to Shanghai and Beijing conveys a conciliatory image. For instance, in June, the White House told the Dalai Lama that while Mr. Obama would meet him at some point, he would not do so in October, when the Tibetan spiritual leader visited Washington, because it was too close to Mr. Obama’s visit to China.

Greeting the Dalai Lama, whom China condemns as a separatist, weeks before Mr. Obama’s first presidential trip to the country could alienate Beijing, administration officials said. Every president since George H. W. Bush in 1991 has met the Dalai Lama when he visited Washington, usually in private encounters at the White House, although in 2007 George W. Bush became the first president to welcome him publicly, bestowing the Congressional Gold Medal on him at the Capitol. Mr. Obama met the Dalai Lama as a senator.

Similarly, while he was campaigning for the presidency, Mr. Obama several times accused China of manipulating its currency, an allegation that the current Treasury secretary,Timothy F. Geithner, repeated during his confirmation hearings. But in April, the Treasury Department retreated from that criticism, issuing a report that said China was not manipulating its currency to increase its exports.

While American officials said privately that they remained frustrated that China’s currency policies lowered the cost of Chinese goods and made American products more expensive in foreign markets, they said that they were relieved that China was fighting the global recession with an enormous fiscal stimulus program to spur domestic growth, and added that now was not the time to antagonize Beijing.

China is not viewed as a trouble spot for the United States. But this administration, like its predecessor, has had difficulty grappling with a rising power that seems eager to avoid direct clashes with the United States but affects its interests in many areas, including currency policy, nuclear proliferation, climate change and military spending.

In that regard, two members of Mr. Obama’s foreign policy team said that the United States’ interactions with the Chinese had been far too narrow in past years, focusing on counterterrorism and North Korea. Too little was done, they said, to address China’s energy and environmental policies, or its expansion of influence in Southeast Asia, South Asia and Africa, where China has invested heavily and used billions of dollars in aid to advance its political influence.

One hint of the Obama administration’s new approach came in a speech this fall by James B. Steinberg, the deputy secretary of state, who has deep roots in China policy. He argued that China needed to adopt a policy of “strategic reassurance” to the rest of the world, a phrase that appeared intended to be the successor to the framework of the Bush era, when China was urged to embrace a role as a “responsible stakeholder.”

“Strategic reassurance rests on a core, if tacit, bargain,” Mr. Steinberg said. “Just as we and our allies must make clear that we are prepared to welcome China’s ‘arrival,’ ” he argued, the Chinese “must reassure the rest of the world that its development and growing global role will not come at the expense of security and well-being of others.”

The Chinese reaction has been mixed, at best. The official China Daily newspaper ran a column just before Mr. Obama’s arrival suggesting that the United States needed to provide some assurance of its own — to “respect China’s sovereignty and territorial integrity,” code words for entirely backing away from the issues of how China deals with Taiwan and Tibet.

In the United States, the phrase “strategic reassurance” has been attacked by conservative commentators, who argue that any reassurance that the United States provides to China would be an acknowledgment of a decline in American power.

In an op-ed article in The Washington Post, the analysts Robert Kagan and Dan Blumenthal argued that the policy had echoes of Europe “ceding the Western Hemisphere to American hegemony” a century ago. “Lingering behind this concept is an assumption of America’s inevitable decline,” they wrote. White House officials shot back, insisting that it is China that needs to do the reassurance, not the United States.

In China, Mr. Obama will meet with local political leaders and will host an American-style town hall meeting with students in Shanghai. He will then spend two days in Beijing meeting with President Hu Jintao.

It seems unlikely that Mr. Obama will get the same celebrity-type reception in Beijing that he received in Cairo, Ghana, Paris and London. China seems mostly immune to the Obama fever that swept other parts of the world, and the Chinese are growing more confident that their country has the wherewithal to compete with the United States on the world stage, analysts say.

“Obama is still a positive guy, and all over the world most people think he’s more energetic, more sincere, than Bush, more a reformist,” said Shi Yinhong, a professor and an expert on United States-China relations at People’s University in Beijing. “But in China, Obama’s popularity is less than in Europe, than Japan or Southeast Asia.” In China, he said, “there is no worship of Obama.”