BEIJING // Even though Barack Obama's tour of Asia is not taking him to China, it will be high on the agenda in the four countries the US president is visiting.
Recent disputes between China and its neighbours have heightened tensions in the region, and many Asian leaders will be looking to Washington to act as a counterweight to Beijing.
The issues other Asian countries have with China are varied. Among them, India has reservations over Beijing's closeness to Pakistan, including its support for Islamabad's nuclear programme. South Korea is concerned with China's defence of North Korea and opposition to joint military exercises with the United States, while relations with Japan nosedived in a dispute over islands in the East China Sea.
What links the concerns, and those of many countries in South East Asia, is a perception that China is acting ever more like a regional superpower. This assertiveness, analysts have said, is pushing China's neighbours such as Japan, South Korea and Vietnam, towards the US.
However, analysts said Mr Obama, while striving to take a tough line with Beijing, must be careful to avoid alienating China, as continued economic and political engagement is vital, especially as tension over the value of the yuan and its effect on US manufacturing remains unresolved.
Although he is not visiting China, Mr Obama is expected to hold talks with the Chinese president, Hu Jintao, on Thursday at the G20 summit in Seoul.
On his four stops, Mr Obama will take with him "a message of reassurance that some kind of balance of power is still in play" in the region, according to Alan Chong, an associate professor in the S Rajaratnam School of International Studies in Singapore's Nanyang Technological University.
"It doesn't necessarily mean that some kind of Cold War-era military containment is in motion as part of the US strategy, but a hint of some form of power balance would be conveyed. That's a given," he said.
Mr Obama faces a balancing act, said Jonathan London, an assistant professor in the department of Asian and international studies at the City University of Hong Kong. Washington must maintain stability in its relationship with Beijing, he said, while responding to domestic and international pressures to take a tough line.
"It's clear the two countries need each other but there's a need for Obama to appeal to domestic constituencies and address concerns about the low valuation of the yuan and … with respect to international strategy, to somehow project politics of firmness towards China," he said.
South Korea also is on a tightrope because, while it would like to trumpet the US-Korea relationship, it must be mindful not to appear to side with the Americans against the Chinese, said Mr Chong.
"South Korea's case is delicate because Seoul cannot afford to alienate Beijing because of its unique diplomatic connection to Pyongyang," he said.
The recent dispute between China and Japan over the detention of a Chinese fisherman, after his boat rammed two Japanese coastguard vessels near the disputed East China Sea islands, has severely strained the relations between Beijing and Tokyo. As a result, said Mr Chong, "the Japanese would have no qualms about appearing to side with the Americans against China".
Indonesia could also benefit from continued US engagement in the region should it develop territorial disputes with China, which could happen if Beijing extended the geographical scope of its claims, according to Mr Chong. China's claims over the South China Sea conflict with those of the Philippines, Taiwan, Vietnam, Malaysia and Brunei.
Overall, Mr Chong said, Beijing might be asking itself if it has over-reached over the past year by taking what many commentators have seen as an overly aggressive stance with nearby countries.
As well as having disputes with some neighbours, China has reacted angrily to recent American efforts to engage in the region. Last week, Beijing dismissed an offer from Hillary Clinton, the US secretary of state, to host trilateral talks on resolving disputes with Japan. American offers to help set up an international process to solve disputes in the South China Sea were also given short shrift by China.
However, before Mr Obama's visit, Mrs Clinton insisted Washington was not looking to gain the upper hand in the region and insisted "it's not in anyone's interest" for the two countries to view one another as adversaries.