U.S. President Barack Obama and visiting Japanese Prime Minister Shinzo Abe met Friday on a wide range of security and economic issues.

However, contrary to Abe's great hope of showing off the "robust" U.S.-Japan alliance and prodding the U.S. into taking Japan's side in its spiralling dispute with neighboring China over the Diaoyu Islands, Washington this time intentionally played down the issue, refraining from clearly throwing its support behind Tokyo.

The U.S.-Japan alliance, the Trans-Pacific Partnership (TPP) and the nuclear program on the Korea Peninsula, instead of the Diaoyu Islands, topped the agenda of the two leaders' talks.

Obama did reiterate the U.S.-Japan alliance was the "central foundation for our regional security and so much of what we do in the Pacific region," but he trod cautiously, not even mentioning the Japan-China dispute in his brief remarks after his meeting with Abe.

On the Diaoyu Islands, the integral part of Chinese territories illegally claimed by Japan, Abe's attitude was somewhat restrained by Washington's snub.

In contrast to his aggressive and rash statements before the trip, Abe claimed he had always handled the issue "in a calm manner." Although this does not match his deeds, he promised to "continue to do so."

Despite stressing the U.S.-Japan alliance for regional security in Asia, Obama particularly cited the two countries' concerns on the "provocative actions" taken by the Democratic People's Republic of Korea, namely Pyongyang's recent nuclear test. He vowed to take "strong actions" in response.

In addition, a brief joint statement issued by Obama and Abe was confined to the TPP, a regional free trade pact pushed by Washington.

It is clear and widely as expected that Abe failed to deliver on his major bid to solicit explicit support over the territorial spat with China, as Washington weighed between a desire to enhance traditional ties with Tokyo against a growing need to cultivate healthy relations with Beijing.

The outcome of Abe's visit manifested the U.S. attempts to strike a tricky balance.

U.S. expert Christian Caryl has said Japan is Washington's most important Asian ally. And as Chinese influence grew, Washington could scarcely hope to manage the shifting balance of power in East Asia without the help of Japan, Caryl said in his article posted on the Foreign Policy website.

But at the same time, the United States hated seeing its highly interwoven ties with Beijing damaged by Japan's rash behavior. The top two economies had been each other's second largest trading partner while the two UN Security Council permanent members need to cooperate on a host of regional and international issues.

"Nor do the Americans want to see themselves entangled in local feuds that could spark a military conflict" in a region critical to the global economy, as the U.S. economy is struggling to walk out of the woods, Caryl said.

In fact, even before Abe's trip, U.S. officials and think tank researchers clearly revealed the U.S. stance by emphasizing diplomacy in solving disputes and tighter ties with China.

On the eve of Abe's visit on Wednesday, Danny Russel, National Security Council senior director for Asia, said the United States wanted to focus on diplomacy between Japan and China to avoid the risk of miscalculations between the world's second and third largest economies.

"No one wants to allow tensions to fester or to escalate," Russel said.

Robert Hathaway, director of the Asia program at the Wilson Center think tank in Washington, said, "Obama will not want to contribute to the impression that already exists in China that the U.S. and Japan are ganging up against China."