The latest studies on second-hand smoke have shown that those exposed to second hand smoke are at higher risk of heart and lung disease. I smoke so I am not promoting hysteria. The adverse medical problems caused by the internal combustion engine can be observed in cities like Mexico City and other major metropolitan areas but Governments are not out to get people to buy a horse and buggy or walk.
I know why the American flag has 13 strips but the number 13 has been associated with bad luck for millinnia, which is why I referred to superstition and not paganism.
As to pornography the "potential" for abuse by extremists is evident in the news since rapists and child molestors are rabid users of porn. So since even a moderate use of alcohol can make you legally intoxicated (and you don't have to be driving to be charged with public intoxication) the principle is the same.
I do not advocate making alcohol use illegal but Governments spend millions on public education while basically ignoring the potential for abuse of porno. Even the Supreme Court has declared as Unconstitutional the laws passed by Congress to legislate child porn. Now porn is in the eye of the beholder and even "soft porn" can be a problem especially for the young since so many commercial ads are aimed at our baser instincts. There is no doubt that "sex sells".