>but you don't need religion to teach them
The ONLY way to teach morals is religion. Because you need something that is uncoupled from the material man to show him the way and an ideal.
You can't have a material ideology to teach people morals becouse they'll just make whatever suits them to be the leading way. "Just be good" isn't a valid way to do it.
If you use god and spirit you can't corrupt the essence no matter how much you try. Even with churches.
Look at the modern left and how much that "independent" value system went. 2 generation and they're full of sociopaths led by their carnal desires.
The hate of religion is by definition marxist becouse it wants to do what you just described. Rip man from his spiritual self and make him an obedient animal.
And "religion" is many things for a marxist. Sex, family, nation, etc. Everything has to go.
And the first step is to erase God.
Then it's just a couple of decades till the civilization falls.