I wasn't initially planning to comment on l'affair Kos, but it doesn't seem to be going away. (If you've been hiding under a rock, Julia has a good summary here. Here's Kos's full explanation of what he was thinking. Here's Teresa Nielsen Hayden's post, the comments section of which I commend to your very close attention.)
I think what Kos said was ugly, but in the thirteen years that I've been online I've seen a lot worse. And, unlike many of the ugly things I've seen people say in blogs, Kos's comments appear to have arisen from genuine pain. If you've always lived safely in the U.S., you're not really in a position to judge him for having insufficiently warm feelings towards U.S.-funded "security forces" who are not subject to the UCMJ or sworn to uphold the U.S. Constitution.
There's been a lot of sanctimonious criticism, to which I will not link, about the inadequacy of Kos's apology. Does anyone really think that if he had apologized and withdrawn his statement, all would be forgiven? Ask Kathryn Cramer. She went too far in her coverage of the Fallujah killings, and posted some unwarranted speculation. In response, she got vile pornography and death threats posted to her comments section. She took the errant post down and apologized profusely, and the hostile comments increased - because, apparently, taking the post down meant that she was trying to hide. She's continuing to receive violent threats, some of them directed at her children.
The hard right aren't interested in apologies or corrections. If this were really about promoting civility of discourse, they'd have plenty to attack on their own side without hunting down people on ours. They want us to shut up, and that's pretty much all that will satisfy them. Whether or not you agree with Kos, or Kathryn, it's important that we not let them be drowned in a sea of right-wing viciousness. They have a right to be free of harrassment. Both of them have my full support.
Remember: you don't have any way of knowing that it won't be you next. Purity campaigns, by their very nature, tend to spread.