We, the people of the United States, in order to form a more perfect union, establish justice, ensure domestic tranquility, provide for the common defense, Promote the general welfare and to secure the blessings of liberty to ourselves and our posterity, do ordain and establish this constitution for the United States of America.
Show me how drug use is not against domestic tranquility; show me how drug use that destroys lives and minds through free, legal use does not do this. How exactly does encouraging drug use through legalization promote the general welfare?
Show me how allowing sodomites to teach in schools is securing domestic tranquility, by allowing these perverts to brainwash our kids and abuse our children. Show me how the normalization of this perversion promotes the general welfare?
Show me how allowing Homosexual marriages secures the blessings of Liberty and promotes the general welfare all the while these perverts have spread an incurable disease to the general population, to those who only had an operation, or needed a bone marrow transplant, or happened to get a needle stick in an emergency room. Libertarians fight for those perverts rights.
Show me how prostitution secures domestic tranquility by ruining families, by spreading disease, and then show me how demanding medical checks of these prtostitutes does not abrogate their rights to do what they please! Show me how the spread of veneral disease and AIDS promotes the general welfare. Libertarians constantly fight for the right to engage in these actions because it 'shows' freedom, and 'doesn't hurt anyone!'
Show me how the spread of pornography, which has been linked to the rape of women by some who have recently viewed it, and the spread of immoral dress and sexual ideas that are rampant in society, on television, and in the pop Queens like Britany Spears, how Playboy models are considered role models for actresses, spokespersons for products, chosen for Hollywood film roles, and tv gossip shows: Show me how all that, which libertarians fought for, has increased the blessings of liberty and promoted the general welfare of this country.
Show me how the immorality that Libertarianism demands does any of these things, secures the blessings of liberty to ourselves and our posterity. Show me how the immorality that Libertarianism demands promotes the general welfare.
Parental laws against these things tried to stop it or at least keep it to a minimum. Libertarians want these laws repealed, so there can be more of these perversions.
Encouraging drug use does not promote the general welfare. You err in assuming that ending the WOD is the same as encouraging use.
Libertarians oppose laws banning "victimless vices," so that government will get its nose out of lots of things where it otherwise will inexorably become everybody's nanny.
I am not entirely sympathetic with this, but I think that politically we'd be better off if we restricted our government bans to obnoxious temptations and publicly visible blights (e.g. drug pushers, public intoxication, etc.). The private sector (churches, etc.) has seriously atrophied while in essence ceding the keys to the kingdom to Uncle Sam.
Pious platitudes for the children how commendable, high morals with no ideals whatsoever. Most who disagree with you, disagree not because of your one-size-fits-all morality, but because there is no institution left able to justly enforce or carry out your plan. A morally bankrupt government can no longer be trusted to faithfully judge the actions of the citizenry anymore than a crack-whore can trusted with the collection plate at church.
Government has abandoned their primary responsibility of protecting the people, as we the people have to step in where government failed, we the people will take a more active role in defining morality. Unless you sport a badge, there is little you can do to stop it.