>>520532102 (OP)
Because Christianity is a religion of weakness. The moral core of Christianity is about forgiveness, compassion and turning the other cheek. You're able to give it some teeth with the metaphysical aspects, but once you remove that, you're left with a moral core that's just about "compassion" and "empathy". It's interesting because Christianity failed us twice, first by existing, priming the west for accepting weakness and then by creating modern liberalism, you see modern liberalism is just Christian morality but without the metaphysical notions of god, heaven and hell. You can see this in the way they frame their moral positions and their arguments (almost all progressive positions start from an "original sin" before offering ways to achieve "salvation"). The suicidal empathy of liberalism comes from the same place.
We can't really expect Christianity to help us any more, at it's core it's a slave morality: a set of moral principles that teach to exert influence by subversion instead of by strength. But that rejection of ones own strength leads to an inability to defend.
And that's where we find ourselves today, a culture that has no real ability to defend itself because all of it's laws and moral fibers are defined using a morality that has no teeth without a metaphysical backing. A backing that very few people believe in nowadays. As an aside, this is why Eastern Europe and the US have had a better time rejecting and fighting back against the suicidal empathy of liberalism than western and northern Europe, plenty of people still really do believe in the metaphysical nature of the morality, they're able to act with the force of that divine right.
Thank you for coming to my TED talk.