Murder of innocents is antithetical to that social safety net. Easy peasy.
I'm not speaking for all atheists. Honestly. I personally don't see any "ultimate justice" as that would require a God to mete it out. As an atheist I see no such thing so I have to assume there is no "ultimate justice". I cannot, therefore, see how an atheist could believe in "ultimate justice" for evil done in life.
But I want to thank YOU for agreeing that your dislike of atheism is the same kind of reasoning that you accuse some atheists of becoming atheists for...they are mad because God didn't give them what they wanted.
This isn't how most atheists function but your earlier accusation indicates that it is indeed how YOU function. In this case atheism is not your cup of tea because it doesn't provide enough punishment for evil doers, doesn't give you everything you want from it.
Honestly I get that. It's comforting, especially for someone who holds onto grudges and hatred really well, to yearn for wrongdoers to be punished in accordance with it. It's a perfectly natural human requirement.
Unfortunately, your argument is exactly the one most holy rollers make and it really doesn't hold water. These people did evil for a very simple reason: they murdered innocent people. One doesn't need a metaphysical structure to understand how that might be wrong. And easily defined as such. There are perfectly rational non-objective reasons for us as a species to all agree this is "wrong".
Again, your arguments all kind of mirror those of hard-core believers. You want "ultimate justice" for evil (which requires a God), you want "meaning" which requires something beyond the physical, you want "objective morality" (again, something beyond the physical).
All of that is fine, but it really does make me wonder why you call yourself "agnostic" when every single thing you find appealing and want for yourself and clearly believe exists would indicate you are hardly without some actual belief in the supernatural.
Incorrect. One can easily put them on trial even without an "objective" morality. Here's an example: humans are social animals that gain a survival advantage from a stable social safetynet. Murder of innocents is antithetical to that social safety net. Easy peasy. No supernatural or metaphysical thing necessary.
Darwinian principles of evolution are about survival and transmission of genetic information, not morality and values .
No one blinks an eye when a male lion kills the cubs of a rival.
Hitler and millions of his supporters thought culling the German nation of Jews, gypsies, disabled people was neccessary for the health and survival of the Aryan peoples. Very few Germans openly questioned this policy.
Both Hitler and Stalin thought slave labor was neccessary for the advancement of German and Soviet society.
Spartans disposed of weak babies.
Cananites and Phonecians thought ritual child sacrifice made perfect sense for their societies.
Twin babies have been killed by various societies because identical twins were thought to be a bad omen.
Your claim that humans just naturally avoid murder because of evolution or because we are dancing to the tune of deoxyribonucleic acid doesn't pass the laugh test, not even for a nanosecond.
The pricetag for being atheist is a belief in subjective morality based on opinions. There is no higher ontological morality that says what Hitler did was wrong if morality is based on opinion or popular vote. Oppression of the Jews would have passed popular vote in Germany in 1938.
We only have the moral standing to hold a Nuremberg trial if we appeal to objective ontological morality that stands apart from human opinion.
The price you pay for being an atheist is to embrace subjective morality. If you are uncomfortable with subjective morality, you better rethink why you are an atheist.
And maybe you're right, that opinion and subjective morality is all that exists. But that is an unappealing price tag to me. That is not a good selling point.
It's fine if you want to hijack the objective morality and values of religious traditions, and just strip it of religious language. But just be honest about doing it.