Secretary of State John Kerry speaks at the Swiss Federal Institute of Technology, or Ecole Polytechnique Federale De Lausanne, in Lausanne, Switzerland after Iran nuclear program talks finished with extended sessions. Snap back? Not so fast. The biggest enforcement provision in the preliminary nuclear agreement with Iran is turning into one of its mostly hotly contested elements. And this debate barely involves Iran. Instead, it concerns the Obama administration’s promise to quickly re-impose sanctions on Iran if it cheats on any part of the agreement to limit its nuclear program to peaceful pursuits. (AP Photo/Brendan Smialowski, File-Pool)