What a joke. Iran has what could rightly be called an impressive navy but that is strictly in a local coastal defense sense. They can "rule the waves" withing view of their own beaches when up against such adversaries as Somali pirates or Iraqi patrol craft or gunboats during the Iran/Iraq war but that's about it. It's a bathtub navy, not a blue water navy by any stretch.
The notion that Iran could "project power" abroad on the high seas is laughable. Sure, they could post a frigate off of Baltimore or New York but what's the point? They don't have the support craft to maintain a flotilla on station for any length of time anyway so it would amount to little more than a weekend sightseeing trip for them.
What it amounts to is they have the capability to hang a pinata by our front porch and hope we come out and whack it so they can play the wounded victim on the PR stage. That's about it.
Offensive capabilities?

If they were insane enough to try they would just be going cape buffalo hunting with a BB gun.