if enough people cared, similar definitions could be made for porn. just like every non-natural death is not premeditated homicide, there are various degrees of porn
more could be done to discourage porn. a lot could be done by private individuals, groups, and companies, if we were free from government forcing us to be "morally neutral" how we could enforce a social stigma.
So the same can be said for just about any other issue in the world (poverty, disease, etc.).
"just like every non-natural death is not premeditated homicide, there are various degrees of porn"
I agree. And that must be a necessity
And while I'm personally in agreement with the Catholic Church's (and Abp. Chaput's letter), we live in a society where the criminal law, while based on Christian values, must be somewhat secular to be compatible with a democracy which upholds freedom of belief.
IIRC, Lord Devlin made similar remarks in 1965, a few years after the infamous Wolfenden Report came out...
That is the moral and proper way to combat porn. Goobermint edicts are not.