Wow, there is a lot of confusion in this thread. And it's no wonder, because copyright is a confusing idea. The trick is to pay attention to what it's called, copyright, the right to make copies.
For a minute, let's ignore the special "fair use" exceptions that have been added over the years, and look at the original deal. You buy a book or tape or CD, you aren't getting the copyright. The publisher who printed the thing you bought is the one who had the right to make the copy you bought, not you. All you get is the right to read/listen/view that copy.
Now, there is the fair use doctrine, which in some respects is peculiar to the US. In the case of music, it was made somewhat explicit by the Audio Home Recording Act. That law grants the additional right (not a license -- you didn't get one of those -- it's a right granted by AHRA) to make backup copies for personal use, and one of the places you are allowed the put your backup copies is on a computer peripheral. That's why devices like the iPod are designed to work the way they do, to take advantage of the special computer peripheral exemption. In general, digital copies are forbidden, and that's the reason you see so few standalone digital recorders (and when you do see them, like DAT and MD devices, they are required to add copy protection).
And yes, with that fair use thing being a quirk of national law, that does mean that devices like the iPod are technically illegal to use in some countries.
There was always the right to lend books and recordings, but not to make and give away additional copies, because no license to make copies was ever granted.
There have also been court decisions that granted limited personal rights to record broadcasts for time shifting purposes.
Since AHRA, we of course got DMCA which took away some of those extra rights if the publisher has added copy protection.
Computer software has always been a little bit different, because it's necessary to make at least one copy (into memory) to make any use of it. That's why programs had to include licensing agreements in the first place. All the other strings that have been added are, well, businesses being businesses.
So anyway, all of that is the reason you can buy something and then be allowed to do so little with it. You really don't own the content.
[edit, never did finish...]
Anyways, where the DRM stuff comes in is because all the rights are tied into making copies, and electronic transfers break the whole concept of delivering a copy to the purchaser. So, the seller in that case has to grant a limited license to copy, because otherwise the purchaser wouldn't have the right even to keep the download. In that light, the DRM schemes being attached to music are typicially more generous than what, for example, CDs offered. The big difference, of course, is that DRM actually interferes with things the purchaser doesn't have the right to do; a lot of the freedom built into traditional media was actually just the ability of purchasers to overstep the rights they actually were granted.
So, that's where all the conflict comes from. It's not that rights are being taken away -- those rights were never really there -- it's that people are becoming upset when they realize how meager those rights really were all along.