I've always found it interesting that death threats are almost exclusively employed by fundamentalists and other reactionaries. After all, you don't hear many liberals threatening to kill someone for saying Martin Luther King was a Communist or that free markets will save the world. Is it because liberals are able to come up with rational arguments and the average reactionary cannot?
The Dixie Chicks got death threats for saying they were ashamed of Bush--now most of the country is.
Anyone helping women abort unwanted fetuses is liable to get death threats--especially in the violence-prone Bible Belt, where some of those threats are actually carried out. Doctors have been murdered by "Pro-Lifers" for reducing the world's misery--for we now know that Roe vs. Wade was largely responsible for the abrupt decline in violent crime a generation later.
We also now know that a homophobe is someone who has homosexual impulses he can't accept. He hangs around gay bars and beats up men who are acting out impulses he's afraid to act out himself. Men who are comfortable with their sexuality are tolerant. Men who are conflicted are not.
A violent response implies that the perpetrator is afraid of the truth. When Putin has his journalist critics assassinated, when a drunk hits his wife, when a homophobe beats up a gay man he's attracted to, it's because they have no answer. An act of violence is an admission that your victim represents a truth you're unwilling to face. To kill your opponent certifies that he or she was right all the time.
That's how I knew Jimmy Carter's book was on target--he got death threats for saying you'll never achieve peace by automatically defending everything one side does while condemning every act of the other.