China got its man back. But the greater Japan's supposed humiliation, the greater the defeat for China and its strategic interests in the region.
Japanese Prime Minister Naoto Kan is now being pilloried inside Japan for displaying weakness. Had Kan's LDP critics been in office, the outcome of this affair would very likely have been the same. But that doesn't matter. The political incentives in Japan now favor a harder line against China the next time another such incursion occurs, which is very likely.
Second, other countries in the region have not taken kindly to China's recent elevation of its claims over the South China Sea to the level of "core interest." China's high-decibel screeching at Japan only reinforces the impression among policymakers in the region that China might now be turning into everyone's problem. And if these countries view China as a problem, a collective response may follow -- the last thing China should want.
The fishing boat incident in the Senkakus does not rise to the level of Munich 1938. But the incident's outcome may be one of the last accommodations China gets before policymakers in the region begin contemplating the need for containment.