And because of this attitude...someday child pornography will be legal as well.
Child porn is quite different than pornogaphy involving adults. The reason that prosecutors don't file charges against regular porn producers is because they have to get a jury to agree that such material is obscene. If we're talking about mainstream porn, that is very difficult if not impossible to do, even in rural Mississippi or Alabama. It seems that the vast majority of Americans, liberal and conservative, believe that images of consenting adults having sex is not obscene.
With child porn, all the prosecutor needs to prove is that the pornographer knowingly filmed or distributed images of underage kids having sex.