Japan occupy Chinese territory ,Diaoyu island,US should shoulder part of the responsibility for that,you know,after world war II your government had mad a big mistake on that issue.
Now,your government should pay more attation to your words and actions.Do not hurt Chinese again and again.Even that Japan is your allied partner but the justice is still there and anybody should sustain it.
If you insist on justice,if you believe in God,if you are a real democracy country,you should let the Japan leave the island at once.