Destroyers, not aircraft carriers, are the modern battleship. They are the most powerful surface combatants afloat. Many are approaching the weight of pre-dreadnought battleships. A modern guided missile destroyer could destroy a mid-20th century battlewagon with ease. If a carrier got into a gun battle with a destroyer, it would be destroyed easily. That is why they need destroyers to escort them.

Any navy without destroyers, is like a early 20th century navy without battleships. Destroyers are the modern battleship, and all naval strength should be measured in destroyers, not carriers or SSBNs. They should be considered capital ships.

The USN has over 100 destroyers and destroyer-based cruisers.