Current debate centers around the question, "Should we protect children from viewing certain material on the internet at the cost of adult priveledges?" The ACLU and like-minded groups say no. They argue that Internet content screening is the responisbility of the parent. If you want to protect your children from pornography, fine, just don't restrain the freedom of speech to do so.
Their solution: Create programs that edit Internet content on an individual basis. Kind of like v-chips that are implemented through the installation of software. These programs wil not be government regulated. The parameters will be set by the user to prevent the usee (children) from viewing "X-rated" sites.
The problem with this is what kind of software/net blocks do you place on computers provided for public use in places like libraries? Suggestions range from having separate computers for adults and children to having acces codes which correspond to the age of the user.
Overall, it seems that there is no concrete solution to this problem. But like the debate on television violence and sexual content, it is more the parents responsibility than the governments.
It comes down to the fact that regulated or not, those who wish to receive "naughty" documents from the web will continue to do so. If such things become illegal in the US, the black market from overseas will continue to flourish.