The US has quite a few shops scattered around the world at all times. The 22nd, 24th, and 26th Marine Expeditionary Units patrol the Atlantic and Mediterranean.
And yet, still all probably hours away from the incident, which renders them going there pretty pointless. Especially when they aren't equipped for these sort of rescue operations like the Coast Guard to begin with.
All you need is the rope to pick people from the water. Not even that.
And some lights to try if it gets dark.
It's not that simple, how can you with a straight face think it's that simple when hundreds of people are in the water?