I think the ability to travel and commit murder have taken a quantum leap due to technology. As such, I am not sure that the numbers mean anything that we can learn from. Before the 20th, mass bombings by air, nukes, widespread machineguns, mustard gas, etc were not really available. If they had been there 1000 years ago, with the almost constant state of warfare in Europe, would they have all killed each other off? I think so. However, I am talking about maybes and ifs and there is no way to prove if I am right or not.
Has there not been an almost constant state of warfare in the world over the past century? Even for us educated and informed Americans, the beacon for the world, we have spent at least 38 of the past 100 years engaged in war.
Anyhow, for you analogy to work, you would have to compare the Hebrews of the OT to the Christians since them; bringing up the almost constant state of warfare in Europe "1,000 years ago" actually hurts your argument with regard to being morally ready for the New Covenant.
Societal norms are not morals. However, they do reflect the true morality of the population. Not the stated or purported morality, but the only real measure of morality, which is the one lived.
'Societal Norms' only reflect the values that are esteemed by certain societies. 'Societal Norms' in the Occident have 'progressed' if anything in an effort to make capitalism even more efficient. Strikes, boycotts, etc. had monetary impacts. Money speaks. Money is not morality.
You don't believe in inherited knowledge? Not exactly sure what you mean by that. Do I think we soak up knowledge in our dna? Of course not. Do I believe that we soak up knowledge from our environment? Yes. I think that if our society decided 100 years ago that women were capable of being more active and voting, then that became a part of our conventional wisdom. The next generation grew up with that understanding. They built on it. Women worked. Were allowed to divorce. The pill. Bra burnings. etc. Till we get to where we are now, where most of us believe that women should be treated fairly and equally. That is incremental progress. Ideas grow and have children.
Society decided to let women vote because it was expedient and efficient; not because anyone felt that women were equal. Today, there are still plenty in America who do not feel that women are equal, nor are African-Americans. In fact, I will be surprised if another African-American is elected POTUS in my lifetime; since, many in this 'morally advanced society' with these 'flourishing ideas' will simply draw an analogy between Obama's Presidency and potentially what will happen if any other African-American holds the Oval Office. I could be wrong; I bet I am not, though.
That being said, that is not why we had the old law. Unless you just want to talk about it with an open mind, I would rather not try and explain it. I really don't think you care. Correct me if I am wrong, but you simply have an antagonistic attitude towards religion and you would rather argue about it than try to learn about it.
I do have an antagonistic attitude toward religion; that does not mean that I am unlearned in the subject. I have yet to hear a coherent argument in which any Christian can reconcile the Old Testament and the New Testament without conceding that both are only to be taken allegorically.
Please, though, explain why it is that an Omniscient, Omnipotent, Omnibenevolent, Perfect, and Immutable being had to affect a radical change in his creation and, in doing so, make his previous admonishments null and void.
While you are on the subject, if you could explain to me how it is that a Perfect entity can create Imperfection without then causing Itself to thus be Imperfect, I would be much obliged and in your debt.