I don't know much about the penetration properties of radiation, but I would imagine high yield neutron or EMP weapons would make staging of S-300's (or equiv.) mobile missile systems quite difficult if not impossible. The problem is KNOWING WHERE THEY ARE when the SHTF. Israel will have to attempt to bathe most of Iran in a radiation blanket if they wish to survive.
I know one thing, we are in serious danger if such a calamity breaks out while Hussein is president.