Barack Obama's first visit to Asia since his inauguration was one of the most disappointing trips by any U.S. president to the region in decades, especially given media-generated expectations that "Obamamania" would make it yet another triumphal progression. It was a journey of startlingly few concrete accomplishments, demonstrable proof that neither personal popularity nor media deference really means much in the hard world of international affairs.

The contrast between Asia's reception for Obama and Europe's is significant. Although considered a global phenomenon, Obamamania's real center is Europe. There, Mr. Obama reigns as a "post-American" president, a multilateralist carbon copy of a European social democrat. Asians operate under no such illusions, notwithstanding the "Oba-Mao" T shirts briefly on sale in China. Whatever Mr. Obama's allure in Europe, Asian leaders want to know what he means for peace and security in their region. On that score, opinion poll ratings mean little.

What the president lacked in popular adulation, however, he more than made up for in self-adulation. In Asia, he labeled himself "America's first Pacific president," ignoring over a century of contrary evidence. The Pacific has been important to America since the Empress of China became the first trading ship from the newly independent country to reach the Far East in 1784. Theodore Roosevelt created a new Pacific country (Panama) and started construction on the Panama Canal to ensure that America's navy could move rapidly from its traditional Atlantic bases to meet Pacific challenges. William Howard Taft did not merely live on Pacific islands as a boy, like Obama, but actually governed several thousand of them as Governor-General of the Philippines in 1901-1903. Dwight Eisenhower served in Manila from 1935 to 1939, and five other presidents wore their country's uniform in the Pacific theater during World War II—two of whom, John F. Kennedy and George H.W. Bush, very nearly perished in the effort.

But it was on matters of substance where Mr. Obama's trip truly was a disappointment. On economics, the president displayed the Democratic Party's ambivalence toward free trade, even in an economic downtown, motivated by fear of labor-union opposition. On environmental and climate change issues, China, entirely predictably, reaffirmed its refusal to agree to carbon-emission limitations, and Mr. Obama had to concede in Singapore that the entire effort to craft a binding, post-Kyoto international agreement in Copenhagen had come to a complete halt.

On U.S. national security, Mr. Obama came away from Beijing empty-handed in his efforts to constrain both the Iranian and North Korean nuclear weapons programs, meaning that instability in the Middle East and East Asia will surely grow. In Japan, Mr. Obama discussed contentious issues like U.S. forces based on Okinawa, but did not seem in his public comments to understand what he and the new Japanese government had agreed to. Ironically, his warmest reception, despite his free-trade ambivalence, was in South Korea, where President Lee Myung-bak has reversed a decade-long pattern by taking a harder line on North Korea than Washington.

Overall, President Obama surely suffered his worst setbacks in Beijing, on trade and economics, on climate change, and on security issues. CNN analyst David Gergen, no conservative himself, compared Mr. Obama's China meetings to Kennedy's disastrous 1961 encounter with Soviet leader Nikita Khrushchev in Vienna, a clear indicator of how poorly the Obama visit was seen at home. The perception that Mr. Obama is weak has already begun to emerge even in Europe, for example with French President Nicholas Sarkozy, and if it emerges in Asia as well, Obama and the U.S. will suffer gravely.

Many media analysts attributed the lack of significant agreements in Beijing to the "rising China, declining America" hypothesis, which suits their ideological proclivities. But any objective analysis would show that it was much more Mr. Obama's submissiveness and much less a new Chinese assertiveness that made the difference. Mr. Obama simply seems unable or unwilling to defend U.S. interests strongly and effectively, either because he feels them unworthy of defense, or because he is untroubled by their diminution.

Of course, most Americans believe they elect presidents who will vigorously represent their global interests, rather than electing Platonic guardians who defend them only when they comport with his grander vision of a just world. Foreign leaders, whether friends or adversaries, expect the same. If, by contrast, Mr. Obama continues to behave as a "post-American" president, China and others will know exactly how to take advantage of him

John R. Bolton is a senior fellow at AEI.