When did this arbitrary period start? With interracial marriage? Women's suffrage?After more than two hundred years during which, in every state of this country, continuously, it was assumed that promoting the moral convictions of a majority was a legitimate government interest--and during which two hundred years the Supreme Court never even suggested anything to the contrary--that Court has arbitrarily decreed that it is not.
As a counter question what is the constitutional grounds for the laws that forbid the practice of witchcraft? Law that are still on the books in many states and local city/county governments. There is a relation here.What you don't want to admit is that the only reason for laws that make a number of sex-related acts crimes is that the majorities that made those laws believe those acts are immoral and unacceptable. If promoting that belief through laws is no longer a legitimate government interest, I'd like to know just what constitutional grounds those laws--thousands of them, in every state--rest on. Please tell us that.
Loving vs Virgina. If SCOTUS ruled that there is no legitimate basis for a state to prevent interracial marriages and has over multiple cases noted that marriage is a basic fundamental right, then what basis does a state have for preventing SSM?There is no constitutional reason to prevent it or require it or anything else, because it is simply not a constitutional issue. And it is not same-sex marriage that needs to serve a legitimate government purpose. That is part of the standard ordinary state laws have to meet in order to survive a Fourteenth Amendment due process or equal protection challenge. A garden-variety state law has to be rationally related to furthering a legitimate government interest.
Social harm is a highly subjective term. We can demonstrate physical harm from alcohol and pot when used and then a motor vehicle is operated and other similar situations. So that indeed does argue for laws restricting activity while under the influence of such substances, while not arguing for the absolute restriction of the substance itself. As to tobacco, there are many other activities that we do not restrict or prohibit that have higher potential health risks than smoking or chew or other products. So the only legitimate restriction of tobacco would be for public area due to the imposition of those who do not wish to be exposed to such substances. The issue of whether or not a business is public or private is for another thread.Anything for which there is NOT any legitimate govt or social harm should be legal. Period. And let's face it....things like cigarettes and alcohol DO cause social harm. Increase public health costs.
On the nudity front, you could show a potential health issue of unconsented exposure with the surface transfer issue. So a restriction of not being allowed on public siting surfaces with no bottoms would be a legitimate law.