The whole idea of having
three four classes of ships that all have the same role bugs me. Frigates, destroyers, cruisers, and battleships all used to have distinct roles. But two things have changed that paradigm forever. One is the advent of air power and the attendant aircraft carrier.
The other is the steady advance of technology, that has made it possible for a single ship to fulfill several roles at the same time. We saw the same evolution with armor. All the various kinds of tanks coalesced into a single concept that brought all the most important aspects together in a perfect form: the main battle tank. And we saw the same evolution with fighter jets. All the day fighters, night fighters, all-weather fighters, interceptors, and even tactical bombers coalesced into a single multi-role fighter-bomber platform.
And it's happened to warships, too. A modern surface combatant (i.e., not a carrier, not a submarine, and not some other kind highly specialized vessel like a minesweeper) has four basic roles, all having to do with the defense of the group:
- Air defense, manifesting as powerful air search and track radars, and a battery of air defense missiles.
- Anti-submarine warfare, manifesting as a hangar, one or two helicopters suitable for sonar and torpedo work, and perhaps a magazine of torpedoes on the ship itself.
- Surface combat, manifesting as a deck gun and anti-ship missiles.
- Land attack, also the deck gun, plus cruise missiles.
Notice that some of the weapons themselves can be multi-role to a certain extent.
Anyway, my view is that there's no point in building anything on the frigate-battleship spectrum that does not fulfill all four of these roles. There's only one real ship in this multi-role, "picket" category. For my convenience, I'll call it the destroyer. Firstly because the destroyer was originally conceived to screen capital from submarines. Over time, it came to be the screening class for the entire spectrum of threats against the group, same role, same name, makes sense to me. Secondly because the destroyer was the first type to become fully multi-role. Thirdly, because compared to WW2 classes, modern destroyers are often cruisers by tonnage, and battleships by firepower.
So nowadays, they're all destroyers. The only real question is how big do you want to build your destroyers. Do you want a baby "frigate" hull, with small magazines and limited ability to perform each of its roles? Sure, if that's consistent with your doctrine and budget. Or maybe you want vast arsenal, "battleship" hulls, capable of screening a carrier group for weeks on end. Maybe you want a mix. A few battleships as group leaders, lots of destroyers to fill out the ranks, and maybe some frigates as lightweight/low-intensity patrol boats.
But really, they're all just different sizes of destroyer. Which is why the Navy's desire for a new battleship class rankles. It's just a larger destroyer. And while I'm pretty sure a destroyer that's too small is useless in all roles, I'm not convinced that making really big destroyers is better than making medium-sized destroyers.
