The simple answer is yes. It's an easy answer: we can live without submarines.
We may still be playing—and it's one of the important roles in the future, if we're talking about conflicts overseas and forward deployment of forces.... If we take the Chinese naval denial strategy, which most observers think is where China is going in terms of their capabilities, we'll potentially have to deal with submarines. But you don't need a submarine to deal with a submarine. There are advanced and ever more sophisticated technologies, remotely controlled technologies, that enable one to deal with the submarine threat.