Iran has tentatively agreed to ship much of its huge stockpile of uranium to Russia if it reaches a broader nuclear deal with the West, according to officials and diplomats involved in the negotiations, potentially a major breakthrough in talks that have until now been deadlocked. Under the proposed agreement, the Russians would convert the uranium into specialized fuel rods for the Bushehr nuclear power plant, Iran’s only commercial reactor. Once the uranium is converted into fuel rods, it is extremely difficult to use them to make a nuclear weapon. That could go a long way toward alleviating Western concerns...