TOKYO — Declaring that "the United States is and always will be a Pacific nation," President Obama launched an Asia tour designed to assure leaders of ally nations that they have a strong U.S. backup at a time of rising regional tension.
Appearing with Japanese Prime Minister Shinzo Abe on Thursday morning, Obama said the "U.S.-Japan alliance is the foundation not only for our security in the Asia-Pacific region but also for the region as a whole."
He later said the U.S. security treaty with Japan "covers all territories under Japan's administration, including the Senkaku islands," but reiterated that Washington did not take a position on competing claims of sovereignty. China has asserted that the uninhabited islands, which it calls the Diaoyu, are part of its territory.
Abe and Obama also discussed the Trans-Pacific Partnership, a proposed free-trade pact that constitutes the other major part of Obama's Asia agenda.
"Now is the time for bold steps needed to reach a comprehensive agreement," Obama said, trying to nudge negotiations on the 12-nation accord forward. No immediate breakthroughs were reported.
Obama and Abe held talks Thursday morning after a private dinner Wednesday at Sukiyabashi Jiro, a tiny restaurant made famous in the recent documentary "Jiro Dreams of Sushi." The leaders had agreed to postpone their formal welcome ceremony and royal reception until they had met one-on-one in a casual setting.
The sushi session opened a week of delicate diplomacy for Obama as he finally makes the Asia trip he canceled last fall because of a government shutdown in Washington.
At the heart of his mission is a complicated task: to promise a strong U.S. commitment to Japan, South Korea and other allies without provoking too much concern in China, which has bypassed Japan to become the second-largest economy in the world. Washington also must be careful about tripping in its allies' complicated web of disputes with China and one another.
"We want to continue to encourage the peaceful rise of China," Obama said, while noting that "all of us have responsibilities to help maintain basic rules of the world and international order."
Relations between Japan and its neighbors are deeply colored by historic grievances, fresh reminders of which arose while Obama made his way to the region. Abe sent a ritual offering Monday to the Yasukuni shrine in Tokyo, a memorial to Japan's war dead that he had visited in December, angering China and South Korea. On Saturday, authorities in Shanghai seized a Japanese ship over claims dating to the 1930s, a move denounced by the Japanese government.
"We're trying to thread the needle between China and Japan," said Charles Morrison, president of the East-West Center in Honolulu. "China is very important to us; we want to engage China constructively in a relationship with us and the rest of this region."
Washington, though, is worried that Tokyo is not "repairing or handling the relationships with neighboring countries very well," Morrison said. "That puts a lot of pressure on U.S. diplomacy." The U.S. in particular needs South Korea and Japan to cooperate on issues surrounding North Korea, he said.
South Korean officials said Tuesday that they had detected signs of stepped-up activity around North Korea's nuclear sites, and White House officials said they didn't discount the possibility that Pyongyang could be planning a weapon test to coincide with the president's visit.
"North Korea has a history of taking provocative actions," White House Press Secretary Jay Carney said. "We are always mindful of the possibility that such an action could be taken.... That is something that they have, unfortunately, done many times."
Although China, Japan, South Korea and the United States have tried, in fits and starts, to work together to effect change in North Korea, the countries have at the same time been challenged by various disputes over territory and air and sea navigation rules.
Beijing has been asserting its power in the region, particularly the last two years, proclaiming the right to interrogate and intercept unknown aircraft in an air defense identification zone over the East China Sea. It also has asserted control over parts of the South China Sea.
China's military also is expanding, while Japan's pacifist postwar constitution has limited its military capabilities. Abe is pushing for revisions that would allow Tokyo to come to the aid of the U.S. or other allies under attack.
Japan and other allies have been seeking reassurance that they have American support in territorial disputes with China, even as U.S. budget cuts have limited the flow of military resources to the region.
"There is a bigger risk now of a military combat situation occurring, even by accident, between China and Japan," said Koichi Nakano, professor of political science at Tokyo-based Sophia University.
Appearing alongside Obama, Abe said "Japan has been walking on the path of peace based on its peaceful orientation in a consistent manner" for the last 70 years.
But in a suggestion of his ambitions to bolster Japan's military, Abe said his administration "intends to continue to contribute to regional peace and prosperity more proactively than ever." He added that he looked forward to speaking more with Obama about how the alliance should look in the future."
Obama, for his part, pledged that as the U.S. modernizes its defense posture in Asia, U.S. forces in Japan would include America's "most advanced" capabilities.
After Japan, Obama will visit South Korea, Malaysia and the Philippines before returning to Washington next week.
Parson reported from Tokyo and Makinen from Beijing.