This one:
Aegis Ballistic Missile Defense System - Wikipedia
They want to intercept missiles with it. And they have lasers too.
Woah there you've done the Bleipriester switcharoo that happens when you're caught making things up. You didn't say Aegis, you said Patriot as seen in direct quote from you below:
Bleipriester =
"Many carriers are around and each has its own fleet of submarines and destroyers mit Patriot AA System."
Aegis has nothing to do with Patriot, and USN doesn't have Patriot so why are you saying "this one" as if Patriot missile is Aegis system? It doesn't make sense. When did the US Navy deploy Patriot missiles on their ships like you claim? There is Aegis on US Navy ships, Aegis ashore, but as far as I know there aren't any carrier battle groups deploying Patriot at sea. Care to explain?