They have not cooperated fully with IAEA inspectors. They have not reported all their facilities to the IAEA.
Their program is shrouded in secrecy, which would not be necessary if they were only seeking nuclear power. Their actions demonstrate that they are either pursuing nuclear weapons or they would like to appear to be doing so.
I think you've hit the nail right on the head. They would like to
appear as it they are pursuing nuclear weapons. In reality, they might never actually make any. They can buy the plans, enrich the uranium, and get everything ready, but its their trump card. If they make the weapons, Isreal
wll take them out, and there goes their trump card. So, what they should, and will do, is get the materials ready to make them ASAP if they ever need them. But, they will not make them, because that will result in fighting, and the overall end of their dictatorship.
It's very smart of them to do this. They hold the pieces in place so the threat is real, but they don't act upon those pieces to fully establish the threat, so the West cannot react to that threat. It's a wonderful case of shadowboxing, and they are doing pretty well for themselves. And, coincidently, it also helps the West.
Our main concern is that the Iranians actually make the weapons. As long as they do not, and they just maintain the peaceful purposes, everything is fine. And if we can start barking at them to not make the weapons, we don't have to bite them because they won't make those weapons.
So, in the end, they will get all the materials ready, and they will have scientists and weapon experts on standby, but they won't go past that point, because there is no need to go past that point.