It happens on a regular basis now. Chinese and Japanese research vessels pass each other and lay down a challenge or a vessel from China comes too close to Japanese waters. Japan has its exclusive economic zone which is protected by international law, according to the Nikkei Asian Review, and to entire Japanese territorial waters one must give advanced notice. From our viewpoint, Japan and China, the two largest economic powerhouses in the region, are now expanding their Navies, and in the coming decade these Navies will surely lock horns.
As Japan and China set their boundries there will be small but sometimes tense confrontations in the region. The exclusive economic zones or EEZs as they are called, have been patrolled both all countries but on July 25, about 120 km off the coast of Nagasaki Prefecture, two Chinese vessels entered Japanese waters – the EEZ – without prior permission.
This is in violation of Article 246 of the UN Convention on the Law of the Sea. And note that these territorial issues have been ratcheted up since 2010 – and we see Japan and China turning up the heat in the future. While both Japan and China are talking, note that China is building a fleet of aircraft carriers and Japan is building more – and very quiet – submarines to protect its recognized territorial waters.