The U S has been saying that for a decade now. There is no real Intel that's being shared that says Iran has nukes. Now, that's not to say they don't have the capability to make a dirty bomb. They do have that capability, but the trigger mechanism to make a nuclear weapon is much different than just wrapping nuclear material around explosives, which is what most people think of when it comes to nuclear weapons. Unless Iran was given that capability it's very hard to figure it out with substandard nuclear and weapons scientists. This is why only a relative few countries actually have nukes. It isn't the overall financial cost of making them, but more a question of scientific and technical know how to make one.
The U S has been saying that for a decade now. There is no real Intel that's being shared that says Iran has nukes. Now, that's not to say they don't have the capability to make a dirty bomb. They do have that capability, but the trigger mechanism to make a nuclear weapon is much different than just wrapping nuclear material around explosives, which is what most people think of when it comes to nuclear weapons. Unless Iran was given that capability it's very hard to figure it out with substandard nuclear and weapons scientists. This is why only a relative few countries actually have nukes. It isn't the overall financial cost of making them, but more a question of scientific and technical know how to make one.