There is good reason for its opacity. Once it were to declare that it was a nuclear power, Iran would face all the international wrath and condemnation that would come with it – including for having violated the international Nuclear Non-Proliferation Treaty (NPT), to which it is a signatory.
"I think it's in their interest to go to the limit, bring their capabilities there, and then – when there are milestones – decide whether to go forward," says Olli Heinonen, the former head of safeguards at the IAEA, now at Harvard University's Belfer Center for Science and International Affairs. "Once you put it down that you have nuclear weapons, you are in a different situation. But while you have the ambiguity and people really don't know, and you have maybe not broken all the rules of the NPT, then you are much better off because you can then get some international support."
If Iran were to become a nuclear power, the most immediate question would be what it means for Israel, where warnings have reached histrionic heights.
"Absolutely nothing will happen," says Martin Van Creveld, an Israeli historian and author of some 20 books on military strategy. "Israel has what it takes to deter Iran, and the Iranians know it."
Mr. Van Creveld is implying that Israel's own nuclear arsenal of an estimated 200 warheads would prevent any Iranian first strike. Israel has the only such arsenal in the Middle East, and – unlike Iran's program – it has never been subject to UN inspection or safeguards.
"Say they build one bomb – it's not good enough. They need how many – 2, 3, 5, 10, 20? And that will take them a long time, so it's all nonsense," says Van Creveld. Iran is "not going to commit suicide by dropping the bomb – or even threatening to drop the bomb – on us."