This year will see the 40th anniversary of the normalization of diplomatic relations between China and Japan. However, the two nations seem not in the mood for celebration.

A series of incidents staged by the Japanese Government have set an unusual tone for bilateral ties since the beginning of 2012. First, local legislators landed on the Diaoyu Islands on January 3. Days later, Japan claimed to name the surrounding islands. In April, far right-wing Governor of Tokyo Shintaro Ishihara proposed to buy the Diaoyu Islands. In July, Prime Minister Yoshihiko Noda joined Ishihara to suggest purchasing the islands and realizing their "nationalization."

The Diaoyu Islands have been Chinese territory since ancient times. Japan took control of the islands during the Sino-Japanese War of 1894-95, which China lost, and placed them under the jurisdiction of the Okinawa Prefecture. After World War II, the United States handed "administrative rights" of the Diaoyu Islands to Japan, in spite of China's objection.

China and Japan have long been at odds over the Diaoyu Islands. Japan has repeatedly taken measures since the 1990s aimed at putting the islands under its control. Tokyo has chosen the battle with Beijing over the Diaoyu Islands this year mainly for two reasons: First, the political situation in Japan is not stable. Strong remarks and actions were made to cater to nationalist sentiments among the Japanese public. Some politicians are seeking more votes in future elections and pressuring the ruling party for more favorable policies. Second, Japan is trying to cope with a rising China and the United States' return to Asia. To maintain its influence in the region, Tokyo aims to deepen its alliance with Washington and cooperate with the U.S. Asia-Pacific strategy. It not only provokes tension with China over the Diaoyu Islands, but also meddles with China's sovereignty issues with some Southeast Asian nations over the South China Sea.

Under the political influence, the general public of the two countries, once hailed as good neighbors across a narrow strip of water, harbors dissatisfaction with each other. A recent survey shows 80 percent of Japanese people have a negative impression toward China. The sentiment in China toward Japan is similar. In addition, around half of Chinese and Japanese believe China-Japan relations are becoming sour.

It is regrettable to see tension, dissatisfaction and resentment build up during this auspicious anniversary. Forty years ago, the two nations realized normalization of diplomatic relations. It was the political wisdom, courage and vision of the older generation of statesmen that opened the gate of cooperation and friendship between the two nations and peoples. Now as Asia is growing into the center of world economic growth, China and Japan need to clear away difficulties and interference to promote the sound development of bilateral ties and cooperation. Japan should take the right step, not only for the anniversary.