Iran hid nuclear material: approximately 400 kilograms of uranium enriched to 60% purity

[Igel]

20. At this point just package it in smaller quantities and distribute it.

Why worry about further refinement for now? First keep it safe and worry about next steps later.

I've read that German scientists under Hitler never actually managed to have the amount of heavy water they needed not because they didn't have it, but because they "stored" a large-ish quantity in railroad tank cars that were always in transit or just sitting in a railroad yard waiting to be moved.

The Germans were in danger of being called treasonous because they didn't want a dictatorial regime to be able to produce an atomic bomb. Nobody claimed they were doing it to keep it from being bombed (in fact, railyards and trains were a valid target, unless it was known they were carrying 'cargo' for the detention or death camps).

Many still think that either they were nowhere close to 60% HEU or that somehow that's what's needed for civilian reactors.