I’d caution against using the word ‘deserve’ so loosely. While you may see it as meaning ‘imperial Japan had to be stopped by any means necessary’, it comes off more like retribution. It comes off like a bloodlust for revenge.

In general, ‘deserve’ should always be followed with ‘because…’. Just saying x deserves y assumes we agree on: what x did, an ethical/moral system, and that y is the best punishment/reward in that ethical/moral system.