Were there any Japanese antiwar groups during World War Two?

I must say I'm not sure. In my light research I haven't found any. Given the diety-emperical divinity, and the societal devotion over the individual evidenced by Kamikazi, I think not. Japan believed they would win the war well into 1943, As long as they held resource rich Manchuria, and controled the Malaysian archipeligo.

Here in the Bay Area Your answer is Yes, however you should know they were arrested for spying. They were caught by a Citizens tip (a youngster ) who witnessed a laundry truck stopped where it shouldn't have been when on his way fishing. His spot was "occupied" by an Asia person taking pictures of "OUR" submarines. Even a 10 year old knows. The rest you can fill in. The sub 's name if my memory still serves me correctly. was Thunderfish . They had a chance to see it for themselves in Tokyo Harbor but were to busy watching their new carrier going to the bottom on launch.