It's of course obvious that the messenger is just that, a messenger. And we all agree that it's not his fault - until we don't like the message. Then everything changes and we need someone to blame, someone to attack and destroy, and of course, collect money from. Whoever sent the message might be far away and it could be hard to even figure out who they are. But the messenger is right there, and his business probably has money that we can take!
The Pirate Bay is one of those messengers. Charged with "assisting" in a crime by being a messenger of information describing where some people are sharing files which in some cases have been copyrighted. These are the facts: TPB does not have any of the files being shared on any of its servers, they never access any of the files and the files never pass through any of their servers or networks. Torrent-files do not contain any of the files to be shared. TPB helps the file-sharers keep track of who's sharing a collection of files. A torrent almost always uses multiple trackers and even before TPB was first brought to court many BitTorrent clients could do the tracking themselves without any trackers.
It's of course clear that TPB haven't committed any crime themselves and they're actually being charged with being the "messengers" of some other crime - that wont even be proven. Of course a large portion of the torrents on TPB describe collections of files that are probably copyrighted but at the same time there are also large portions of torrents on TPB that are perfectly legal to copy as much as anyone would like.
So we shut down TPB because some people use it to share copyrighted content, and everyone else will just have to go somewhere else, hoping the "bad" people wont follow. But some people are still using BitTorrent in illegal ways. Well, we'll just have to force the ISPs to ban BitTorrent altogether and all the innocent users will just have to come up with an other technology. Again, hoping the "bad" people wont follow. But they do, so there's nothing left to do but to ban Everything and then if someone wants to use the Internet for Anything then they first have to apply for a license and prove that they wont be bad.
Welcome to the police state where you're guilty until proven innocent. Of course it's impossible to prove innocence (since it's the absence of something, only by knowing about Everything can you prove it's not there). But if you don't bother any of the rich people then they probably wont throw you in jail.
Is that the kind of society we want? No it's not. That's why there are laws that clearly say that the messenger is Not to blame. Of course, the music- and movie-industry doesn't care about those kinds of laws, and you can be sure that they're working hard on getting rid of every single one of those pesky laws that protect the people but stand in the way of their expected profits.