Couple of things to keep in mind with this:
1. Reactor coolant (if it's not water), is not something Iran can domestically produce.
2. Natural uranium is not useable for bomb-making. In fact, you can handle it with your bare hands. It has to be refined to sort out the impurities before it can even be processed into reactor fuel. And even reactor fuel isn't potent enough for nuclear bombs.
Only when enough is processed into 80% (much better if you really want an explosion) U-235 can nuclear bombs be considered. And to get there, you need to use centrfuges to seperate out the U-235 from the rest of the uranium. Large numbers of centrifuges, a lot of power to operate them, specialized machinery and goods, and a lot of time.
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BTW: Iran has it's own uranium deposits. Any argument that claims we need to stop this to keep uranium out of their hands is automatically invalid.