Ok, stupid question because the Internet is not going to break. But suppose a global EMP were to take out all of the electricity and electronics in the world, and thus the Internet breaks. My guess is that many Bitcoin will be lost (web wallets, even computer based wallets that are not backed up), however the code of the blockchain would not be lost, and Casascius coins and Titan coins and other physical bitcoins could be bartered (even at a high price) with the understanding that when the Internet does get fixed the first thing that coders would do is restore the blockchain.