The Sankei Shimbun reported Tuesday that Japan and the US have reached an agreement on their joint use of US military bases in the Pacific region. According to the report, the Japanese Self-Defense Forces are planning to station forces alongside US troops in the Philippines. A base on Palawan is most likely to be the first choice for their stay.

Since the 90s, confronted with changes to the security situation in East Asia, the US and Japan have intensified their military cooperation and gradually extended it outside Japan. However, considering the sensitivity of the US-Japanese agreement relative to the South China Sea disputes, China should be wary of Japan's expansion.

Japan's interest in the South China Sea disputes is obvious. Its Self-Defense Forces jointly conducted a military drill with the US and Australia in the South China Sea near Brunei last July. They also joined the US-Philippines military drill this month. Expanding the influence of their military forces overseas is a means for Japan to prove its international clout. The move is important to shore up domestic confidence as Japan's growth has remained stagnant for a long time.

For a while now, Japan has been hoping to alleviate its pressure on the Diaoyu Islands dispute by intervening in South China Sea disputes. It is not in Japan's interests for the South China Sea disputes to be solved peacefully.

The US is refocusing its strategic attention toward the Asia-Pacific region and this provides Japan with a good opportunity. US allies in Asia, such as Japan and the Philippines, all try to gain benefits by flaunting their connections with the US.

Japan is also intensifying its military cooperation with some Southeast Asian countries. It plans to supply patrol vessels to the Philippines and assist Manila in training its coast guards. It is these adjustments that have led to the Philippines' inflated arrogance and its tough attitude in provoking China.

As a country which devastated Southeast Asia during World War II, Japan improved the negative impression it left there by providing official development assistance and investing in these countries. From the overall perspective, economic cooperation is the top priority of Japan and these Southeast Asian countries. China has surpassed Japan in terms of being an economic growth engine to the region.

Now neighboring countries are bonding together to challenge China while trying to secure its economic benefits. How far can this marriage of convenience go?