The event has been a disputing issue on the internet.
Some of the inhabitants insist on rejecting construction of mosque, because it is associated with terrorism. In Japan, Middle East countries are famous for wars and Moslem. So, some Japanese don't have good impression on Islam.
By the way, I agree with construction of mosque in this case. The reason for resisting construction is all but emotional problems as this. Theoretical reason can't be found in this case.
We have to think about the way to persuade them into understanding Islam.