Where is it you see me making an argument for it being okay? It would be equivalent and thus not naked revenge. Please stop trying to make up a position I am not taking.
I'd argue the fear of death is justifiable. if it was I, I'd gladly trade death for sitting in prison. and obviously most people in that situation agree with me.
I am not sure what you mean, to be honest. I will use a stupidly extreme example of what I am reading in your sentence: Because we are more civilized than cannibals in Papua-New Guinea doesn't mean we shouldn't eat humans. Forgive me if I am misreading your statement, but yes, the fact we are trying to be more civilized means exactly that we should not kill out of Justice. We are too stupid and arrogant to see the future and what it will bring, and to use such a final solution is hubris. But we have all discussed this before, so I am not sure we will ever convince one another.
I'm suggesting that just because the punishment doesn't fit the crime that still doesn't mean that it isn't justifiable.
I have a problem with him living a long fruitful life in prison. He'll watch TV, eat three meals a day, live in A/C, exercise, have friends, communicate with his family, cheer for his favorite team, go on the internet, laugh at jokes, you name it. Frick him. He killed and maimed people. No amount of rehabilitation will make that ok. No amount of prison will make him a contributing member of society.
He would be isolated outside of the general population. Unless, we are asking for prison justice to be the ultimate solution?
Does he deserve to die for his crime? Yes. Then it is justice. If he does deserve to die for his crime, and he doesn't die, it is therefore injustice.
Let's get cynical. How much does life in prison cost, and who of those who obviously and blatantly commit crimes meriting a life sentence are worth that price tag? We waste far too much time/$/energy on the utter asswaste of society. We need to find the cheapest method of execution - not the show-stoppingest, not the most genteel - and ramp it up. JMO, haven't really thought it through too far.
Let's put one bomb that's guaranteed to blow his leg off complete with dangling artery like the poor soul that got his leg blown off by that psychopath. Let him suffer for a while. Then a few days later put him in another room with another bomb that kills him like he killed 8 year old Martin Richard. I would be ok with that.
How about instead of a deserted island, we take all death row inmates, and put them in a big arena with swords and lions. And then we have them fight.
In some circumstances, that would be a practical action I would have no problem with. But this is the 21st century and we are the United States of America. He's already in custody. I wouldn't have advocated for going to any great lengths to take Bin Laden alive, for example.