The oft mentioned .xxx domain.
It is a sweeping and powerful weapon, and it would not affect any non-public computer or access point.
Require all porn sites to present anything they wanted... literally anything, but... if they violate the rule, they are blocked permanently by all ISPs.
If the ISPs whine it's too difficult, they get filtered out too.
Problem solved.
Not really. Who will comply? The porn sites? Haha! Who will pay to enforce it? Thousands of new porn sites are constructed every week! ISPs could never keep up with the requirement to constantly block every new site that pops up. It would require armies of employees. They can't even keep child porn off the net. How on earth are they going to regulate the millions (yes, millions) of "legitimate" porn sites out there?
That being said, I'm sure someone will make a .xxx domain into law soon. And it will have *zero* effect on internet pornography except that some politician somewhere will be able to say he did something.