laying it out, KH is a great series but agreed that the storyline doesn't make sense unless you think of it this way. the first is straightforward enough (bad guy wants power, good guy beats bad guy, subplots galore, finale). In chain of memories, the nobodies were erasing soras memories which made him believe they were holding the girl he liked hostage, so going through them to rescue her is also somewhat justified in a gaming sense (Mario Bros plot basically). Kh2 has the nobodies collecting hearts by hurting the friends of the main chaaracters, thus messing with the worlds order and also attempting to kill or destroy some of the disney characters who the main characters know (i.e. xaldin attempts to make beast into a heartless). Basically, the only way Sora and Co.'s actions against the Nobodies can be justified is simply because they wanted to kill him, stole his girlfriend, and were using him to get hearts. add this to the fact that nobodies are technically are not supposed to exist, and sora was essentially killing off very annoying viruses. yes their story is extremely tragic and i honestly think Axel could have been the strongest organization member if he used his power better (i loved that guy), but i digress, they are emotionless (no matter how much they pretend not to be) and always initiated the fight first, or did something to piss Sora off, etc.