[mrbluecoat]

Non-weapon fissile material Thorium is an option.

[MertsA]

Thorium isn't fissile, it's fertile. All thorium reactors work by breeding that thorium into uranium.

[AnthonyMouse]

Commercial reactor fuel isn't weapons-grade to begin with.

[XorNot]

This cannot be stressed enough: commercial reactor fuel is 5% enriched. Bomb material is 90+% enriched.