This is a great find! And it really makes sense, especially since the political leadership in Iran is currently fractured. There's a huge power struggle between Ahmadinejad and Khameni, and in one of the Persian language newspapers that I was reading the other day, it said that they were even arguing over things such as women covering their hair. Ahmadinejad wants to relax the laws to allow women to show more hair, and Khameni and his backers wanted punishment for women who showed more hair.
Anyway, my story was a bit off-topic, but I think you bring up a great point that there hasn't been an "okay guys, we're going for the bomb" type decision because of the leaders butting heads.