Let's start from the top.
You're perfectly allowed to try and compose a rational argument in favor of the death penalty, and I wish you good luck, because I've certainly never seen a (sound) one before.
Putting a criminal to death means there is zero chance of him doing those horrible acts again, either by escaping or being let out. It means not spending resources keeping them alive and healthy in the already overcrowded and expensive prisons (assuming it didn't take years more worth of trials and mountains of legal paperwork, but that's another issue).
And there are issues which only some positions hold the monopoly on rational arguments, like gay marriage and yes, the death penalty. I'm not going to try to maintain some ethereal golden mean.
You are doing it again. If those are, indeed, both purely moral issues, than neither side has "the only rational argument". Rational implies logic, and logic is a process, not the end result. There is no such thing as objective morality.
I also never said anybody was hate-filled, or monstrous.
You very
heavily implied it.
I do understand the pro-death penalty side. If somebody killed somebody I cared about, I'd likely desire their blood as well.
You understand part of the rhetoric. To be fair, though, that's all anyone ever talks about or even mentions in passing.
But just because one desires something doesn't make it a sound argument for what policies the government should enact.
I agree, though we differ considerably on certain moral issues.
So many ninjas. this thread is moving fast tonight.
edit: I did a quick search and found
this article on objective morality (or rather a lack of it). It pretty much sums up my view of the topic (except maybe part of an opinion stated near the end, depending on how it is interpreted).