I don’t think it’s about Russia at all for Japan. It’s about China and their recent escalations in Taiwan, south china sea and east china sea.
The only thing that really has to do with Russia is that they showed the world that near peer wars are still a thing and that China is a potential threat for all East Asia.
China is not a potential threat for East Asia, China is a potential threat to the US and the US wants to control East Asia and Japan works a checkpoint to keep that region in place.
I think actually if USA is serious about a war with China they will only command Taiwan to jump under the bus and declare independence, the actual country that will fight against China like Ukraine against Russia will be Japan (and SK’s Army). Taiwan can be cut off from USAs wunderwaffles supplies by NPLA and its economy is not as strong like that of Japan if they want them to fight until the last Japanese ;) . Also the mental preparation is already there (where in Taiwan they would rather wonder after a while why they should fight other Chinese).
Saying Japan or SK would fight is a weird way of putting it, since they would be following orders from the US, but I guess I agree with what you say. This scenario is an unwinable one since they also have not been cultivating a strong movement as was the case in Ukraine, where the CIA has bern training units since the Maidan Coup, and also Taiwan being so isolated and so much smaller. Plus China would have Vietnam and NK as allies which would difficult a lot the Japanese and South Korean armies.
