The Chinese have sent two patrol ships to reassert its claims, and the Japanese Foreign Minister Koichiro Gemba has repeated the line that the purchase served " peaceful and stable maintenance of the islands" and that " we cannot damage the stable develpoment of the Japan-China relationship because of that issue. Both nations need to act calmly"
T he Chinese defence ministry spokesman replied, accusing Japan of " using all kinds of excuses to expand its armaments and repeatedly creating regional tensions".
This is happening at a time when the Chinses are very concerned with their economy which is slowing down. Japan is a key eceonmic partner and China will not want to act in a way that jeopardises this relationship ( perhaps this is the very reason that Japan has acted at this time) They are also in the midst of their once-in a decade leadership change and the fact that the heir-apparent has not been seen for a while, even postponing a meeting with Hillary Clinton ( whether it is illness or a behind -the scene struggle for power)is causing concern.
The Chinses will not back down and Japan is sending its Asia department chief to Beijing for talks to "avoid misunderstanding and lack of explanation on the issue".
Its touch and go and neither side want to lose face. Both sides are fiercely proud of their territorial integrity and sovreignity and that's why this is troublesome. Also China has other disputed territorial claims in the South Chima Sea and will not want to be seen as weak and compromising. Interesting times.
Update...19/9/12
The past week has seen continued protest across China and this has raised economic fears. Trade between these two economic giants, which is worth $340 billion is being affected and this is good for neither the skaky Japanese economy or the slowing Chinese. China exported $148.3 billion to Japan and imported $194.6 billion worth of goods from Japan. While both countries are heavily dependent on trade with each other, Japan stands to lose more. The Chinese who are going through their 10 year leadership change cannot afford any additional pressure on its economy.
The protests have resulted in many Japanese firms, like Toyota, Honda, Panasonic etc. closing down operations. This cannot be allowed to last. Neither countries can afford this but cultural values and historic wrongs (this is the anniversary of the brutal Japanese occupation of the 1930s), have caused emotions to run high. The next week will be important in determining the real effects.