I can't even count the number of comedy central stand-up specials I've seen that casually make jokes about absolutely horrific things that destroy lives. Jokes that play on children dying, slavery, the holocaust, rape, murder, pedophilia, torture, etc. I guarantee you that both you and I both know someone (or are one person removed, at most) that has had their lives destroyed by one of these things, or something of a similar caliber. Does that mean that none if these jokes can be funny, in any context? If so, I'd say you'd be hard pressed to find a single comedy special that counts as funny; virtually every comedy special I've seen makes light of one of these horrific things in some way.