Following up on what I told yesterday
, since there seems to be no technical way of solving the spam problem, could there be a political/legal way?
Of course not. Most spammers are already outside the law, since they push illegal substances, or are simply emailing scams. Why should they be affected by a law more or less?
The only way of solving the spam problem is changing email itself. It's not clear what and how to do it. Besides, it's not clear either whether we would like to do it. If you can stop spam, you can stop many other things: political activism, for instance (in fact, in many cases spam is used for political activism).
What can be done, then? Just find your optimal mix of spam ASPs, spam by-content and by-origin filter, whitelists/blacklists/graylists, and enhance your speed pressing the delete key.