Growing economic interdependence is another factor why China has become very important for ASEAN member states. With the exception of the Philippines, almost all ASEAN member states have China as one of their top trading partners.

Under President Xi Jinping, China has intensified its development policies toward ASEAN - the first focuses on increasing direct investment and building infrastructure, especially high-speed trains, and the second is aimed at narrowing the income gap among ASEAN member states. Such an approach will expedite the integration of China's southern region with mainland Southeast Asia beyond the ASEAN community by 2015.

Occupying the center of mainland Southeast Asia, Thailand views itself as the strategic transit point among South, Central and Northeast Asia.

Thailand may be one of the oldest US allies, but Thai leaders now feel that their country has been left out in the cold because of Washington's rebalancing policies. The US' reluctance to engage Thailand - citing the country's messy political situation - has further dampened the 180-year-old friendship. By agreeing to meet Thai leaders for only five minutes on the sidelines of the UN General Assembly meeting in New York, Obama made it clear the place Thailand occupies on the White House's priority list. As a result, despite being eager to attend the General Assembly meeting, Yingluck Shinawatra canceled her planned trip to New York.

For the past few months, Thailand and China have been discussing one of the region's most important and strategic projects that would in the future link China with Singapore by rail, making a 3,000-km journey possible in 24 hours. Thailand knows its commercial and strategic importance as the main transit point both for the East-West and North-South corridors.

For the time being, the rail network will connect Kunming in China's Yunnan province with Vientiane in Laos and Bangkok in Thailand. The proposal is to extend the rail network to Kuala Lumpur in Malaysia and Singapore. There have been some hiccups over the terms and incentives of the proposed plan. But given the regional leaders' determination, the project is expected to go through.

China's growing regional and international influence also fits into Thailand's overall strategic policy toward major powers in the 21st century. As a permanent member of the UN Security Council, China's support for Thailand's UN-related activities, including its candidacy for the non-permanent Security Council seat in 2016-17, is pivotal. Gone are the days when Thailand relied on US support only for its multilateral role. Under Yingluck Shinawatra, Thai diplomats are searching for new friends that can help increase Thailand's profile and expand its export market.

Closer ties with China, both economic and strategic, will also send a strong signal to the US that Thailand is willing to move ahead with new partners that offer mutual benefit. Interestingly, even some top Thai security experts support the idea of deepening strategic partnership with China, along with holding joint military training programs and exercises, and increasing arms procurement.

Thailand's strategic blueprint for 2013-16, being worked out by the National Security Council, could reflect this new imperative.

The author is assistant group editor of The Nation in Thailand.