Americans have been sold an image of the US being an omnipotent presence, due to its Navy. It is a legitimate question to wonder why a relatively weak, long embargoed country has the power to control the waters when the US has spent a pretty penny on all these warplanes and aircraft carriers.

If little Iran can prevent the US from being able to establish security in a little straight, it (ideally) shatters that image and causes some soul searching for what US taxpayers are buying with the military.