Wired magazine has an interesting article on cyber-attack and possible responses, particularly a wartime and peacetime responses:
Last month Marine Gen. James Cartwright told the House Armed Services Committee that the best cyberdefense is a good offense... The general isn't alone. In 2003, the entertainment industry tried to get a law passed (.pdf) giving it the right to attack any computer suspected of distributing copyright-protected material.... Of course, the general is correct. But his reasoning illustrates
perfectly why peacetime and wartime are different, and why generals
don't make good police chiefs.