> We "ban" things from school kids all the time, though: Pornography, gambling, smoking, alcohol, R-rated movies.

And no one really pretended that these cases were cases of "banned books".

The problem is when authority bodies (school, government, ...) start to include, in these "normal non-appropriate" books other books not because they have bad societal consequences when the reader is not mature enough, but because they don't like the content for ideological reasons.

I think it would be a very bad faith argument to argue that reading Maus will lead to people less socially adjusted.

And, sure, some "banned" books may be inappropriate. But as soon as these authorities have open the doors to arbitrary banning books, they poisoned their own well: maybe under "normal" evaluation this book should be removed from the list, but they removed it "the bad way", they failed the process, and therefore the ban itself is illegitimate.

It's a bit like the procedural miscarriage of justice: if you mess up when arresting someone, they can be freed even if it turns out they were guilty. Or in a more topical subject: the Fifa can reverse some decision, but if they do it in the context where they received phone calls from the US president, then it's a big failure in the process, even if a "normal" re-evaluation should indeed have concluded to reversing the decision.