Again, the issue here is not the retroactive judgment and punishing of past acts by private citizens, something which no one here is arguing that Paul Hill had any right to do.
It is a matter of human beings acting to stop someone who is about to murder other human beings.
As I said earlier, if Paul Hill acted in the belief that he had some authority to punish John Britton's past actions then he was wrong. But that's emphatically not what Paul Hill said he was doing.
What Paul Hill accomplished was heightened security for abortion-givers, and a tool for pro-abortion forces to paint the pro-life movement as hypocrites and crazies.
How can we call ourselves pro-life, and kill in the name of life?
If God wanted to stop abortion, He could do it with an afterthought...but He's given us the gift of free will, and that free will MUST BE the weapon employed to stop abortion, not guns.