Assuming that an EMP could wipe your hard drive, memory, BIOS, maybe even the microcode on your CPUs etc, they could screw your computers up.

Solutions are offsite backups, writing your keys on paper, burning your wallet backup to a CD.

Individual wallets are susceptible if an EMP is strong enough to damage primary storage. Backups that are on media that isn't susceptible (which, I believe, includes flash drives that are not receiving power at the time of the pulse) would of course survive.

Because the transaction network is quite decentralized EMP would have to hit pretty much the entire planet to actually destroy it, though a more local EMP (such as an entire major technological country) would probably screw up a lot of mining, thus at least temporarily slowing down block generation quite a bit.

LOL! Yes, that was my first thought but, assuming I was able to survive that and the subsequent fallout (pun intended), I would like to know that my bitcoin holdings were safe and secure.

I don't think they're worth all too much if half the internet is in range of EMP blasts. Otherwise, just have an encrypted backup on a server elsewhere.

Anyways, try not to live where there's a high chance of a nuclear war.

1. Would an EMP affect consumer-grade optical storage?
2. Would an EMP affect an optical 'master' disk, the kind that professional duplication companies would have?

Anything an EMP could do to bitcoins it can also do to banks...

You mean it can effectively empty the safe?

EMP = game over for ALL industries relying on electronics.

My bitcoins are safe because they're on a Paper Bitcoin Wallet.  (see sigline)