Justine Sacco made an offensive comment. But, frankly, the reaction to her comment is far more concerning. The internet hate machine -- the explosion of tweets, blogs, articles, and inevitable rape and death threats -- it's too much. How long until the angry mobs result in someone being hurt or killed?

Justine Sacco made a mistake. A big one. She tweeted a racist joke: "Going to Africa. Hope I don't get AIDS. Just kidding. I'm white!"

Her comment was offensive to people in Africa, black people, people with HIV, and a number of other groups.

I am not defending her comment, in any way. She should not have said it.

It was a joke. A thoughtless, cruel joke, but a joke nonetheless. This doesn't make it okay. Again, I am not defending her comment.

However, it does make it presumptuous to call her racist. Telling a racist joke -- particularly publicly -- indicates a lack of sensitivity to others, but it doesn't necessarily indicate that one is racist.

Can you honestly say that you're never told or laughed at a racist joke, a sexist joke, a homophobic joke, or another offensive joke? Do you have friends who have? Would you judge them or yourself as harshly as you've judged Justine?

She shouldn't be let off the hook for this. Given that she's in PR, firing her was probably appropriate.

However, the mass explosion of hatreds towards her was over the line. She's already lost her job. She's been publicly humiliated. She's probably lost a number of her friends, who don't want to risk associating with her. Her professional reputation has been destroyed, for a long time (and possibly for good). And, if this is like other incidents, she's probably facing rape and death threats. That's usually how it goes.

There is something deeply wrong in the world when we think that someone being guilty of one thing justifies any and all mistreatment of them. We can and should call out racism and inappropriate behavior, but we also need to keep our reactions in line with the incident.

The internet hate machine scares me far more than tasteless jokes.