+8
I don't think condemning terrorism/murderers is something you are going to be banned for here. Quite contrary, you may get repped. Haha. Anyone who kills innocent people is a sick f*ck and should be condemned.
Now, the site is not rigorous when it comes to stating your opinion or believes. To be honest, I don't know what Yoda would do if, say, a Nazi saying Jews have to be killed registered here and spewed his beliefs in threads about it, but I'm pretty sure if you're not into any extremes, you are free to post here. If you go overboard, you will get warned. Don't worry, nobody gets instantly banned from MoFo. Maybe except for spammers and bots.
Anything that has to do with sex, or is extremely graphic is not welcome here. Mainly the visual stuff (photos and videos with nudity, for one, but I wouldn't risk now and post some extremely gory stuff neither), but also the text saying some nasty stuff. Oh, and bad words are alright as long as you don't overuse them (they're being censored anyway), but remember, never offend anyone using them.
I believe the reason for most of these is that MoFo is a free-to-visit site and potentially a little kid can visit it. Then, he enters a random thread and reads about Captain Spaulding frollicking with Sexy Celebrity. Potentially, a little kid can as well visit a porn site, but yeah, that's some explanation.
Short version: Don't be afraid to post. If me, Spaulding and Sexy hasn't been banned yet, it only means it's not that easy to get banned.