To be quite frankly, carrier aren't too useful to them when they have ICBMs that can deliver nuke payload to every South Asian country.
Just because you have nukes doesn't mean you want to use them in a military conflict!
http://en.wikiquote.org/wiki/Starship_Troopers#Chapter_5
There can be circumstances when it's just as foolish to hit an enemy city with an H-bomb as it would be to spank a baby with an axe. War is not violence and killing, pure and simple; war is controlled violence, for a purpose. The purpose of war is to support your government's decisions by force. The purpose is never to kill the enemy just to be killing him...but to make him do what you want to do. Not killing...but controlled and purposeful violence.