The problem is when you make a mistake and now an Iranian plane is in the water. Part of the job of the armed forces is that they stand and handle the risk far more intelligently than we would, i.e. they don't react in terror constantly.
Three responses up though someone is just suggesting that a sailor with a shotgun could take down one of the drones that was hovering close over the helipad.
That negates the possibility of misidentifying a plane as a drone, or hitting anything unintended, or of any risk of taking down a plane at all.
There's a wide gulf of responses between that and firing off an anti-aircraft missile in a "using a bazooka as a flyswatter" kind of application.