This is why any student of history is against SOPA. We believe that it does not protect the rights espoused in the Constitution. We believe that it may be abused in the future.
Some people, such as yourself, seem to believe that this would never happen. You seem to think that because there is a need (in your view) for copyright holders to remove "owned" content, that we need a law like this. And further you seem to believe that its ok to have such a broad law, even though it may be open to such abuse.
UMG is just demonstrating why the founding fathers were right and why you are naive and short-sighted.
Here's the thing: if UMG wasn't actively doing it, you'd still be naive and short-sighted. You'd still be an "asshole", in your words, and the founding fathers would still be right.