Also note that Iran does have an ICBM of sorts. They have a space launch vehicle, capable of putting maybe 600kg in orbit. Anything that can achieve orbit can also be used as an ICBM. The US tends to operate on the assumption that it can bomb abroad without return fire. That may have just changed. The US has never attacked anybody with significant missile capability before.

The symbolic value of Iran hitting a target in the US, even with only a small conventional warhead, would be considerable. Washington, D.C. has some drone and missile defenses. But the rest of the east coast is not protected much.

Iran could also attack the US with drones launched from a small ship off the US east coast. Roughly the same technique Ukraine just used on Russia, using some small expendable ship instead of a trailer.

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