Look at this way. It's as if the Feds passed a law that states, if a library puts Peggy Noonan's latest book on the shelf to be checked out, it must first cut out Chapter 4 with a razor blade.
Is that something Congress should do? Is it something the Constitution permits Congress to do?
That was the legal question before this court.
I guess my real problem is that libraries are publically funded in the first place. That fact creates these problems. In this case, the rationale Congress should take is that the computers are open to the public, which makes it very difficult to assure that minors are not illegally viewing porography on the public dime. Many stores are required to keep sexually explicit material behind the counter. Does that hinder adult access? Yes. It could be argued that an adult may choose not to buy the porno if he/she has to go into a "back room" or ask the sales person to fetch it behind the counter, thus hurting the producer. But, can the material still be bought? Sure. Its just that a minor's access has been restricted by placement and supervision.
Im the last person who wants Congress making any new laws and restricting anything, but the fact that the Feds have no authority to fund libraries conplicates everything.