The US Navy, specifically carriers, are the most important thing that the US does. They not only provide national
security, but they provide economic security as they provide safety for shipping lanes. What they do is literally unprecedented in the history of the world. It's amazing.
I make fun of the navy all the time, but what they do is unmatched. Without their toys, there is no way they'd be able to do what they do. There is a lot of waste in the military, but carriers are money well spent.