Freedom to Tinker introduces a great way to understand the implications of current pushes to extend copyrights: Pizzaright Principle. This litmus test is pretty straightforward, replace the intellectual property term under discussion with ‘pizzaright':
Pizzaright – the exclusive right to sell pizza – is a new kind of intellectual property right. Pizzaright law, if adopted, would make it illegal to make or serve a pizza without a license from the pizzaright owner.
I highly recommend that you read the article. It isn’t long, but it brings the core of the matter to the forefront in a way that is easy to understand, and easy to explain to others.