Spamwar's worst mistakes being recapitulated by the copyright wars

My latest Guardian column, "Copyright enforcers should learn lessons from the war on spam," looks at the fallout from the failed tactics of the spamwar and asks how the entertainment industry plans on doing any better trying the same tactics on an even grander and more savage scale:

Content-based filters

These were pretty effective for a very brief period, but the spammers quickly outmanoeuvred them. The invention of word-salads (randomly cut/pasted statistically normal text harvested from the net), alphabetical substitutions, and other tricksy techniques have trumped the idea that you can fight spam just by prohibiting certain words, phrases or media.

Unintended consequence: It's practically impossible to have an email conversation about Viagra, inheritances, medical conditions related to genitals, and a host of other subjects because of all the "helpful" filters still fighting last year's spam battle, diligently vaporising anyone who uses the forbidden words.