The critical question is whether the risk of military conflict between Japan and China as a result of the hardline policy will continue to overweigh the growing amount of loss from self-restraints. There are two problems. First, the loss from provocation over the Senkaku, namely a risk of losing peace and prosperity, is invisible until the friction escalates to an actual conflict. Second, the loss would be undervalued if one side or both sides believe that the hardline policy is not likely to invite the actual clash, or the local clash, should it happen, will not escalate to a major conflict as the other side will back down.

China seems to think that Japanese government, even under hawkish Prime Minister Abe, will not physically exclude the Chinese government vessels as long as they penetrate gradually. A total of 522 Chinese government vessels intruded the territorial waters around the Senkaku Islands since September 2012 to August 2016, but the JCG has only repeated warning and there has been no clash. If the Chinese believes that Japan’s inaction will continues, they do not have to worry about the escalation in the first place.

What about Japan? Tokyo has been traditionally cautious about the risk of escalation. But it must draw a line somewhere. There is a growing possibility that that the Japanese government believes the China’s response to be limited if Japan takes material countermeasures as I quoted earlier.

Contrary to our intuition, China’s has refrained from using force in the ocean for a long time. The latest example of the exchange of fire by the Chinese military was in January 1988 with Vietnam at Johnson South Reef, the Spratly Islands. Although the Vietnamese casualty was considerable, the battle was limited in terms of duration and field.

As for the Chinese coast guards, their vessels have crashed deliberately onto the Vietnamese fishing boats to sink them in the last few years. In May 2014, they turned the water canon on vessels of Vietnamese maritime police in order to “protect” an oil-rig in the disputed sea area. Intriguingly, however, they did not seem to fire gun then.

Chinese fishing ships are sometime also regulated by foreign authorities. For example, there have been at least three skirmishes with Indonesia so far this year in the waters off the Natuna Islands. On March 19, the patrol ship of Indonesian Ministry of Marine Affairs and Fisheries intercepted a Chinese trawler and arrested Chinese crews for illegal fishing. The Chinese Maritime Surveillance vessel intervened to ram the Indonesian ship and recovered the trawler next day. On May27 and June 18, the Indonesian naval ship fired warning shots against the Chinese fishing boats for suspicion of illegal fishing, and arrested the crews. Although the Chinese Maritime Surveillance rescued an injured fisherman in the latter case, they seemed to refrain from taking further vigorous measures against Indonesian vessels.

These facts require careful readings. But it would be possible to insist that the Chinese government does not always use force in the skirmish over maritime incidents, and are cautious in having their coast guards confront the military of other country.

If China thinks that Japan will not escalate the situation as long as China gradually raise the tension, and if Japan thinks that China will not uncontrollably escalate the response against the countermeasures it takes, the possibility of actual clash will be increased. Once Japan and China clash, nobody knows if they can really avoid an escalation. Two countries have a history issues. Both the Japanese and the Chinese people have a sense of rivalry and dislike each other. Prime Minister Shinzo Abe and President Xi Jinping are known to be strong nationalists. It would not be impossible, but difficult to expect self-restraints from both sides.

Prime Minister Shinzo Abe and President Xi Jinping held ａbilateral meeting in Hangzhou, China on September 5, 2016. They agreed to accelerate discussions between defense authorities to promptly begin operation of a maritime and aerial communication mechanism as well as to resume negotiations regarding the development of natural resources in the East China Sea. But these are the promises agreed several times in the past and have never realized. Who believes things change for the better at last? One thing is clear.

I have to argue that it will be unrealistic to expect the two countries to build a relationship of mutual trust. As seen in the Cold War era, however, leaders who dislike each other can share a sense of impendent danger. Only the mutual recognition of the huge cost of a clash and the actuality of its happening can deter the catastrophe. The Japanese government should give a very straight warning so that the Chinese government understands it is crossing the red line over the Senkaku Islands. It should tell the Chinese that it will consider taking more proactive countermeasures in the context of the sovereignty of the Senkaku unless Beijing stops its provocation in the East China Sea. At the same time, Abe should give up emphasizing value-oriented diplomacy, and send a clear signal that Japan wants to coexist with China in the 21st century. For example, Japan can join the Asian Infrastructure and Investment Bank, and propose the establishment of an institution modeled after U.S.-China Strategic and Economic Dialogue. Admitting that we have no good solution, we must continue to find a way out.