And no, the U.S. does not have enough interceptors to prevent that from happening. Absolutely not. Too many defensive points across a vast area. They need to cover the entire Persian Gulf + sea-adjacent land in the Persian Gulf monarchies, northern Iraq, Israel, Jordan. They need to cover some areas in Yemen / Red Sea.
They also need to fly sorties over a mountainous country the size of western europe (3 times the size of Ukraine).
They need to take out MRBMs, SRBMs and their smaller launchers, take out the cruise missiles, take out the drones and other type of loitering munitions. This is in addition to destroying Iranian security / military C2, ballistic missile manufacturing & assembly facilities. They need to destroy nuclear facilities & targets associated with them.
Remember when Trump fired 80 tomahawk-cruise missiles on Syria in his first term? They struck that airport. Within a week, they had repaired the damage and it was up and running. Think of all of the munitions that Russia has fired on Ukraine, a country 1/3 the size of Iran. Yet most of Ukraine actually looks completely untouched by the war.
Let's not underestimate the amount of munitions that is needed to destroy large countries.