There are limits to libel laws as a result of the First Amendment. I understand your confusion/question, but that's why I bring it up -- there's a lot of disagreement over how to interpret these speech protections and lots of people weigh the issues involved differently. From OP's description at least, it's a bad ruling for people who care deeply about freedom of expression.
Sadly, most people only care about scoring points against those they disagree with politically. Even at the cost of these freedoms.
