I have to say I'm definitely not a fan of this whole "to explain is to defend" or "to understand is to sympathize" line of reasoning. It reminds me of after 9/11, if you said that al Qaeda knocked down the towers because they were upset about US troops being stationed in Saudi Arabia, and they opposed the pro-Western regime in Saudi Arabia and the secularist regime in Iraq, then you were somehow defending the terrorists. Instead, you have to say they did it because "they hate our freedom." It's enforced ignorance.
If I say that a bank robber or drug dealer or Enron executive committed his crime because he wanted to have more money, there's nothing offensive about that (other than the perhaps offensive obviousness of it). But if I say that al Qaeda committed its crimes in response to US policy in the Middle East, or that Vick committed his crimes in part because he grew up around people who thought dogfighting was cool, then somehow I'm defending al Qaeda or Michael Vick? It doesn't make sense.
I think it's rooted in this need some people have to see people who do certain things as non-human. So we might describe dogfighting or terrorism or torture or the like as "inhuman," or we might describe (as has been done in this thread) Michael Vick as a "monster." Good people are praised for their "humanity." My problem with all of this is that it ignores what we know about humans, which is that many of them are cruel, stupid, cowardly, etc.
Someone (maybe author and JREFer David Wong, but I don't remember) pointed out something I found interesting. If you start talking about bin Laden's hobbies, his favorite flavor of ice cream, his first date, stuff like that, it can offend people! Why should this be? It's because we need bin Laden to not be human. Humans have favorite ice cream flavors. Monsters orchestrate terrorist attacks. Never mind that you're not defending bin Laden one iota by talking about his personal life - merely showing that he is human is seen as a defense. It's the same with Michael Vick. If you talk about the culture in which Vick grew up, the forces that shaped him, or what motivated his crimes, you're talking about him as if he were a human. Humans have motivations. Monsters fight dogs.
What I feel we shouldn't forget is that humans are a very diverse group, and capable of evil. Hitler and Stalin were every bit as human as MLK and Gandhi.