For the cost of 100 drones at $2,000 each, they can shut down the shipping lanes, and our multi billion $ ships can’t do much.
What happens when they build and launch thousands?
Their launching sites, warehouses, barracks, and nearby buildings get vaporized.
And then the EW systems knock down the drones.
Right now Ukraine shoots down more than 95% of all Iranian long range drones. And they aren't using modern AA systems except in a few areas.
What happens when US troops launch hundreds of thousands of drones back at them?
Have you watched what happens to Russian infantry when even a few drones are working against them? It is painful to watch some guy in a firefight, hiding behind what he thinks is cover and then a grenade drops right on top of him.