Reason's For Japan's Aggression During the twentieth century, Japan has been in an almost constant state of aggression against her neighbors. While some would say this aggression was initiated in reaction to western bullying and imperialism, this is false. Instead, Japan's aggression can be attributed to its feeling of superiority to other nations and to its lack of natural resources. During this period of unjustified aggression, Japan committed horrible war crimes against its enemies. An example is the horrible atrocities committed in POW camps or the gutless and coward-like barbarity of such events as the Death March