"Radiation hardened" has a multiplicity of meanings. The stuff we sold, IIRC, was designed to cope with charged-particle bombardment (solar wind, et cetera). The chips for nuclear missiles and warheads require the ability to withstand a higher-than-average neutron flux during their regular service life and brief exposure to EXTREMELY high neutron flux during the flight of the missile to the target.
The two forms of shielding are radically different--charged particles are stopped by a Faraday cage of sufficient strength, while neutrons (having no electrical charge) can only be stopped by using enough low density material (hydrocarbon-based resins and the like).
P.S. Here is something to scare the daylights out of you.
Yellowstone caldera, big deal. Asteroids, big deal.
China and N. Korea have been working on getting rockets that can carry small payloads into outer space ready.
Know why?
It's because those small payloads are their new GPS system.
America's overpowering military is possible due to out GPS systems and technology, and is also totally dependent on that technology.
If you want to beat AMERICA, then you must put up your own GPS system, and then disable the AMERICAN SYSTEM.
Other nations (besides China and N. Korea) are helping,investing, and will be watching this feat being accomplished.
One must find out a way to destroy the US GPS satellites without destroying the CHINESE ones. Now I see how. AND....... we are asleep at the wheel.
The stuff we sold, IIRC, was designed to cope with charged-particle bombardment (solar wind, et cetera).
So, they got the chips that could be used in GPS satellites, not nuclear missiles?