Shooting Jeffrey Dahmer would be murder.
"Vengeance is mine, says the Lord. I will repay.."
Your presumption is huge that God told Roeder to murder anyone. God does not instruct people to violate His laws.
I think you are mistaken. Don’t you believe that God wants us to fight for him? I believe that in God’s eyes, Roeder brought justice and stopped Tiller’s mass murder spree. You can believe differently, but I don’t think you can with any real authority.
What makes abortion so dangerous is that it sucks in people who are otherwise good to doing the work of evil or at least accepting it. Satan has learned since the Nazi’s and Communists from the twentieth century. I am wondering if you thought it was murder for soldiers to kill Nazi’s? To stop the murdering of innocent people? Is it a moral issue that is seperate because it involved government decisions? Are you then placing government in the role of a God? Would you agree that it was ok to kill jews if you had lived in nazi germany? Would you have said that it was murder if someone had killed a concentration camp captain and the camp shut down?