The first part of your post, I wholeheartedly agree with. The fed is, and has been, trumping states rights since the turn of the century ( it started with the 17th amendment, but that is a whole other discussion ). Immorality is a relative term, subject to the beliefs of the particular person using the term. Do I agree with drug use, no. Do I agree with prostitution or pornography, no. Do I want someone dictating to me what morality is, or how I should or should not act, no....laws like these are subject to the whims of the person who actually can control these things, and I do not want anyone telling me or dictating to me what is moral and what is not.
Would you interfere with a pedophile raping another persons child? Wouldn't you be violating his rights to freely express himself? Wouldn't he have the same right to his own moral values as you? It has nothing to do with you, right? So, what would you do? Deny him his right to his own moral values, or save the child because of you own moral values? Is there a line? Who would decide the outcome there were no moral norms agreed upon?