What could the Japanese possibly do to take revenge?
Mosques in Japan will be attacked. Hijab’ed or niqab’ed muslim women will be spat upon or cursed or not given seats on Japanese trains. Stuff like that. Any muslim kid in a Japanese public school will be hazed and called a ‘terroristo’. Japanese will tend to spout off their frustration and anger in that manner. At the extreme, you could expect some extreme imperialist fascist (yakuza aligned) group akin to the S.A. in their sound trucks, throwing a molotov cocktail or two at prayer services. That is why Japanese national police are on guard against retribution and the Japanese islamics are playing the C.A.I.R. card. I think that is about the limit as to what Japan can do. It is a shame.