France Won't Rule Out Military Strike on Iran

It takes 90%+ enriched uranium to produce weapons and 1-5% for an electricity reactor. Apparently, 20% is to produce medical isotopes (U235 being a good neutron source(1)) or for some specialized naval reactors.

It's not yet sure if the Iranians really want to make a bomb or just want to show the capability of building one. Unfortunately, the sanctions and threats of war do nothing but entrench those currently in power there.

(1) There are ways to produce neutrons other than by enriching uranium, like particle accelerators.