It helps to keep this tragedy in perspective. For instance, how many of you know that 25,000 people suffer horrible, violent deaths by firearms in the U.S. every year? Or that over 30 million people have been killed in the crossfire of political violence since WWII?I also question the idea that only people who have emotional or physical distance from a disaster can enjoy black humor about it. Clearly we don't have many ER personnel or emergency workers (ie firefighters, cops, paramedics, etc) on this forum. I have family members who work in those fields, and they have some of the blackest humor I've ever heard, and I've already heard some very grim jokes about 9/11. And laughed. And no--we aren't animals for doing it.
You aren't going to see the jokes the emergency workers clearing out the rubble are making anywhere on-line or off. Those folks don't generally share their jokes with "civilians" because they know the reaction would be just what you are seeing here. Dismay, hand wringing, etc etc. Personally, I find the jingoistic, nationalist, racist jokes much more offensive than grim jokes making the rounds about the event itself. And always do.