Key Point

For those who seem to think the Iranian program was only set back a small amount or not at all. 

Lastly, as Iran starts thinking about digging up that 60% HEU and rebuilding its program, it now has to contend with the almost certain possibility that Israel and/or the United States will strike it again as those efforts begin in earnest.

The timeout works because the child knows the consequences of future misbehavior. Yes, Iran can continue toward the bomb. However, the people who must do it knowingly put a target on their back (and are incentivized to snitch to Mossad). Plus, the Iranians risk doing the work only for it to be blown up again.