"The nukes should only target liberals and they cannot leave any radiation behind"
That's the beauty of EMP, it can be set off at a very high altitude leaving little to no radiation behind. It doesn't kill people directly, just every single device with a microchip. No more cars of any kin, electricity, fuel, medicine, internet, air conditioning, refridgeraors or freezers, - you get the idea. Starvation, sickness, and violence in the streets will kill off more people than a bomb could.