There must be dozens of backups around the globe in multiple data centers that are protected from this kind of catastrophic events.
Also, I thought EMP will only destory RUNNING electrical devices. A harddrive that is off, should still be working right? That would mean that a huge part can still excist, atleast partially.
As I understand it, an EMP creates a wave of electrons in any medium that can hold electrons (any conductor). Of course running electronics are more sensitive to such a wave, but any sensitive conductor (eg the pathways through an integrated circuit) would be influenced by the wave. The way I imagine it is like how magicians in movies move water - or how them moon moves water in the tides. An EMP is like an extra moon appearing a few kilometers away and creating a gigantic tidal wave in the oceans, and then disappearing, leaving the tidal wave to wreak whatever harm it may. But we don't have an ocean of electrons anywhere, just pools and a long rivers (power transmission lines). A 50-foot wave going up or down a river will damage a lot of pumps and other plumbing devices not designed to handle that kind of pressure.
Several other comments have confirmed my feeling that this concern is similar to worrying about getting hit by an asteroid; something so unlikely and with such consequences that this particular consequence isn't too important to consider, and for which people have prepared despite this fact.