Copyright enforcement and the Internet: we just haven't tried hard enough?

On Tuesday, Mother Jones blogger Kevin Drum suggested that we don't have effective copyright enforcement on the Internet because we just haven't tried hard enough:

Something that's good enough to provide a measure of IP protection that works for the vast majority of non-supermen and isn't too unwieldy. Is that really any more unlikely than the invention of the internet itself? I'm not sure why.

This is not something you want to believe if, ideologically, you're opposed to IP protection because you think that digital content is fundamentally different from meatspace content on the grounds that making a digital copy of something doesn't reduce anyone else's ability to use their copy. But neither does copying a book. That's never been the point of IP law. It's always been about the income stream an author can get from selling copies of his or her work, and that's exactly the same in the digital world as it is in the physical world. The arguments in favor of IP protection are much the same in both domains.

You might not want to hear that, but just because you don't want to hear it doesn't mean it's not true. The truth is that IP protection in the digital world might very well be possible. We won't know until we try, making a whole lot of mistakes along the way. If you want to argue that IP protection is a bad idea, then fine. Make the argument. But don't pretend that your preferences are also technological certitudes. They aren't.