Is this the old "I am a sinner so you must be a sinner" argument?
I think it's an understanding that short of keeping children away from the computers in a library (thus making it an "adult space" -- Why is the idea of "adult space" and "child-friendly space" so dificult to understand?) so they can't see what's in the screen or teaching them to always avert their eyes, if someone is viewing hardcore pornography on the computer and they look at the screen, they are going to see it. This goes right back to my question. Do you see any problem with exposing young children to hardcore pornography?
I also want to know if you think having sex in public spaces like a library should be banned and, if so, on what grounds. If it's OK to view pictures of people having sex in a public library, why is it not OK to actually have sex in a public library?
"Is this the old "I am a sinner so you must be a sinner" argument?"
I never heard of any such argument. I suspect it to be a straw man.