What would happen to ETH if atomic bomb exploded in space (Worldwide EMP)

In somewhat 1970-2000 cold war there was a plan to take out all russian electricity by exploding atomic bomb over pacific ocean(or i cant remember) which would cut off all communications and so on, near and in russia.

Question here – wouldn't disturbing half of world's magnetic field cut off all ETH wallets? (Not 100% sure about magnetic field but something similar)