So we have a deal and at least some details will be released this week. The deal should be evaluated on what levers it leaves the US to prevent Iran from building a stockpile of uranium five years from now which is approximately the earliest plausible time that Iran may find itself without exploitable US vulnerabilities in neighboring countries.
The US wish list for a deal would be that a lot of uranium, enough to bring Iran's stock from around 2500 kgs to well under 1000 kgs, leaves Iran up front. Then Iran commits to either slow its production or contribute to some form of fuel bank outside of Iran to keep it LEU stock at that low level. Then the US holds most of the shipment of medical reactor fuel as a guarantee that Iran actually stays under the specified limit for a long period. I've read of delays of up to two years before delivery. These were all probably terms of the October "take it or leave it" deal offered by the US and France.
The Iranian wish list is about the opposite. Iran wants to give up as little uranium as possible and certainly to be free to replenish its LEU stocks. It is not absolutely critical that Iran's stock grow this year, but no deal could be accepted that would even set a precedent that later Iranian leaders are not able to build a stock.
So I guess what I'll be looking for as details are released are: 1) how much LEU leaves Iran and when; 2) is anything done about Iran's replenishment rate; and 3) can the US use the return of fuel as leverage and more broadly does the US get any new leverage over Iran's enrichment program.
I have a substantial amount of trust that if Iran's government accepted a deal it does not hamper Iran's nuclear program and in fact that it does not impact in any long or even medium-term way Iran's nuclear capability or "Japan option". So the important element is 3) does the US get new leverage to pressure Iran to restrain the growth of its nuclear program in the future. I'm pretty sure the answer is no.
We'll see the details as they emerge.
