We are the French in 1870

In 1870 Spain had asked the Prussians if they had a Prince would would be willing to serve as the King of Spain.  No Prussian was remotely interested, but the French were horrified.  Had a Prussian Prince been so willing, they'd have been stuck between two Prussian Kings.  So the French demanded of Prussia they they promise to never in the future ever allow on of their Princes to even consider taking the Spanish Throne.  Like the French, today we are demanding that even though Iran has no plans to get the bomb, we must do something, probably bomb them to prevent a nation that doesn't currently have any intention of getting the bomb from ever doing so.