Nuclear facilities do not need to be nuked people. They are in point of fact their own worst enemy. Sabotaging the system can be done with a computer virus and/or physical sabotage of the cooling system and is extremely easy to accomplish once you compromise the facility's security measures. Special forces troops the world over train for just such missions. There is absolutely no need for nuclear weapons to be employed to create a Chernobyl or Three Mile Island with Iranian characteristics. Brains over brawn.