As true as that is, when us mods feel like a situation is getting out of hand, then we step in. We deal with situations on an individual basis. It's not our job to police and correct every single post, we count on posters to try and behave and react to one another on a mature basis. In all honesty, in the great big world of the web, calling someone an "idiot" once is hardly online harassment. While I do question Chris's choice in words, and agree that perhaps he shouldn't have called you an idiot, that single infraction is not enough to get him banned. We mods discuss bannings very seriously, everyone voices their opinion, and then the powers-that-be make the decision based on the discussion.
I was not aware at all of any editings on Chris's part, it never came up in our discussions, but perhaps he edited them not, in fact, to be sneaky and get away with them, but because he realized what he was saying. That's part of why we have the edit feature; so you're not stuck eating any words you wrote in a split-second fit of rage. ;D You could have edited or apologized for any of your posts, but you didn't. That's your decision. Admins & mods only consider banning as a last resort, in reaction to repeat and serious infractions of the above ToS quote you posted.
So yes, maybe a slap on the wrist for Chris. He did go there first this time, as you've pointed out, but to be honest, your own posts seem like you are trying to get a rise out of him on purpose. For instance, posting policially provocative images in non-political and neutral threads. (I might also not that you brought Chris's and Terry's names into the argument in question before Chris made the post you are referring to. That can be seen as provoking or you trying to start a fight.) You said, "I never insult or provoke", but for the record, you have insulted and provoked many a time, and used very harsh language towards other members, so that's not quite accurate. If that was true, you would never have been banned in the first place. I can bring out the quotes if you so desire.
Please know that any major decisions are not based on one person out to get you- all major decisions are discussed democratically by all mods and admins as a group, and as far as I know Chris never went behind your back to try and make you look bad. (And I need to point out that you didn't have to post this in practically all the active forums, that's a little unnecessary; this thread and the one in politics is plenty to let us mods know how you feel.)
So, overall, thank you for bringing this to light and letting us know how you feel. You do have a point, but be aware that a single, less severe infraction is probably not enough to get anyone banned. Us mods & admins will discuss anything we feel we need to, and we will continue to monitor the situation closely. We value you greatly on the forum, you bring a lot of great opinions and ideas, so know that we all try to be as un-biased and fair as we possibly can when it comes to issues like this. Believe me, any major decisions are not based on N2's (or anyone's) political opinions.