Iran seems fully capable of launching missiles -- from the ground, air and sea.
Their issue seems to be guidance technology -- whether they'll go where they're supposed to go.
Granted, a ship complicates the issue -- accurately establishing launch location, relationship to the target, adjusting to any pitch or roll, etc.
However, if said cruise missile is nuclear-armed, close will do. The point is made whether the missile strikes the capitol dome...or Baltimore Harbor.
The risk is defined by three questions:
1. Could the Iranians develop a nuclear warhead?
2. Could they, or their proxies, launch such a device toward the American mainland from a cargo ship?
3. Given the ability, would they conceivably do so?
In each case, isn't the answer "yes"?
Guidance technology that can handle high accelerations, Its much more complicated than just lobbing a ballistic missile in the air and it lands where-ever it lands.
You see today's news story about that shooting in the Columbia Maryland Mall? FNC spend a lot of time on it, with little info to report.
That's in my general area. I go to that mall every-so often. I had my watch battery replaced there recently.