Whither aircraft carriers? Some years ago a former colleague broke down carriers’ historic missions to discern whether they remain adequate unto their tasks in an age that has turned fiercely hostile not just to flattops but to all combatants that ride the sea’s surface. Early on, during the interwar decades, naval commanders regarded carriers as an adjunct to the battleship fleet. These “eyes of the fleet” would launch rudimentary scouting planes to espy a hostile fleet from a distance, help commanders redeploy the fleet to amass a tactical advantage, and spot the fall of shot to bolster the accuracy of gunfire aimed at the foe.

As naval aviation matured, it became feasible to repurpose the carrier as a fighting ship in its own right. New aviation and weapons technology transmuted flattop’s air arm into its main battery, allowing the ship to strike hard across heretofore unthinkable distances with a modicum of precision. That let carrier task forces act in “cavalry” mode, venturing into hostile waters to raid enemy naval bases or logistics before retreating swiftly over the horizon. The hit-and-run sallies launched early in 1942, when U.S. Pacific Fleet carriers struck into the Marshall Islands, then sent Army Air Force warplanes to bomb Tokyo, are prime examples of carriers acting as nautical cavalry. Once the nuclear age downed, flattops reprised their role as raiders for a time, except they would deliver a pulse of atomic rather than conventional firepower against an antagonist.

Or a superempowered carrier could spearhead the fight for “command of the sea,” Mahanian shorthand for sweeping hostile fleets from sea and sky. In this capacity the carrier is a capital ship, a vessel boasting the offensive and defensive might to outgun peer capital ships. A sea force that wins maritime command by defeating a rival fleet, says naval historian Alfred Thayer Mahan, wields “overbearing power.” At most enemy maritime forces can make a nuisance of themselves. They cannot effectively obstruct friendly use of the sea or make use of maritime communications themselves.

Winning maritime command is Job 1 for any oceangoing fighting force. Traditionally that’s a job that falls to capital ships.

And then there’s the “airfield at sea” mission. The victor in the struggle for maritime command can do as the leadership ordains, whether it’s shutting down the enemy’s overseas trade to bring the economic hurt; blockading hostile fleets in port; opening new expeditionary theaters to stretch enemy defenders thin; or, of supreme importance, providing logistical and fire support to forces fighting on dry earth. After all, people live on dry earth, so in the end that’s where wars are won or lost. Carriers could reprise their historical missions from World War II, Korea, Vietnam, and the Persian Gulf, helping the U.S. Army and Marine Corps prevail in ground engagements. That’s a relatively static mission, demanding that flattops remain in the vicinity of an operation so its aircraft are in range to tender support. The drawback is that remaining more or less static makes the carrier’s whereabouts predictable, exposing it to attack.

A task force’s defenses must be stout for a carrier to act as an offshore aerodrome.

Lastly, there’s the “geopolitical chess piece” function, chiefly in times of peacetime strategic competition. Moving carrier forces around on the map represents a time-honored way to telegraph intentions and political resolve, discomfit prospective foes, give heart to friends, allies, and partners, and help recruit third parties to the cause. Carriers are implements of foreign policy in a way no other ship is.

That’s a solid taxonomy of naval-aviation missions. Now, when carrier critics ask whether the aircraft carrier has a future, they’re usually referring to U.S. Navy nuclear-powered supercarriers, the eleven behemoths that bear the weight of U.S. naval strategy while consuming an inordinate share of shipbuilding budgets. The latest nuclear-powered flattop, USS Gerald R. Ford, set back taxpayers about $13 billion. And that’s just the price tag for the hull. Outfitting it with planes, ammunition, and stores demands another hefty sum.

Flattops may still render good service in some of these modes. They certainly remain geopolitical chess pieces, a key reason foreign navies and governments covet their own carrier fleets. They can perform a range of peacetime missions, from humanitarian and disaster relief to mounting a presence in contested seaways. If equipped with long-range uncrewed aircraft, they could discharge scouting and command-and-control missions in combat. Etc. Yet there are ample grounds to question whether supercarriers remain battleworthy when arrayed against a peer navy backed up by anti-access air and missile forces operating from land, complemented by missile-toting submarines and surface patrol craft prowling near-shore waters.

In other words, their prospects are doubtful in the operational and tactical circumstances they’re most likely to encounter.

Most important battlegrounds lie within reach of anti-access weaponry. Sea power is no longer just for navies. It’s for navies, marines, armies, air and rocket forces, and even coast guards and maritime militias. If carriers—and, it’s worth noting again, this also goes for major surface combatants and amphibious transports—can’t operate within the “weapons engagement zone” rippling out from enemy coastlines, chances are they can’t accomplish their tactical and operational goals.

They’re a wasting asset.

If a carrier can’t perform its battle functions—whether it’s a toe-to-toe fight for maritime supremacy, raids into enemy-held sea space, or supplying air support to landward operations—it’s likely to command dwindling support among U.S. lawmakers and the larger electorate. Mahan’s contemporary and occasional foil Julian S. Corbett explains why. Corbett reviews the “constitution of the fleet,” partitioning a navy into three broad functions. One, there are capital ships, brawny ships of war that duel other capital ships in high-seas battles. The armored dreadnought was the capital ship of Corbett’s and Mahan’s day; the carrier has enjoyed that status since World War II.

Two, declares Corbett, bluewater navies operate a “cruiser” contingent. Cruisers are smaller, lightly armed warships, inexpensive by contrast with capital ships, that exercise command of the sea once the battle fleet has wrested command from the foe. Cruisers are affordable in bulk. They—not capital ships—scatter out to police important sea routes, protecting friendly commerce while squelching hostile mercantile and naval traffic. And, Corbett hastens to add, exercising command is what a navy exists to do. Fleet battles are merely a precursor, albeit a pivotal one, to what really matters.

In short, the battle fleet is merely the guardian of the cruiser force, which is the true executor of naval strategy. It controls vital waters.

And three, there’s what Corbett dubs the “flotilla,” a host of even smaller, short-range craft that perform administrative duties in inshore waters. In Corbett’s lifetime, newfangled weapons technology, sea mines and torpedoes in particular, endowed the flotilla with hitting power against enemy battle fleets that came within reach. Submarines and surface patrol craft could give battleships and cruisers a bad day. There’s a kind of symbiosis between the flotilla on the one hand and the cruiser and capital-ship contingents on the other. Flotilla craft fan out in littoral seas to guard the coast in concert with shore-based firepower. Effective flotilla warfare liberates heavy fighting forces to roam the high seas, winning and exercising maritime command.

Corbett and Mahan saw the OG access-denial strategy come into being. Access denial has gone into overdrive since their day.

Here’s the rub. Americans invest in the carrier fleet because they regard the carrier as the U.S. Navy’s premier fighting ship, worthy of lavish expense. In turn they expect the flattop to play an extravagant part in naval warfare, scouring disputed waterways of peer navies such as China’s or Russia’s. If access-denial forces working with increasingly modern enemy fleets kept U.S. carrier forces out of the thick of a fight over Taiwan, for instance, ordinary citizens and their elected representatives could legitimately question whether carriers were still worth their eye-goggling price tag.

They might balk at the expense.

In effect, then, the onward march of technology, tactics, and operations may have demoted the nuclear-powered aircraft carrier from capital-ship status to something humbler. Crudely speaking, the carrier may now belong to the cruiser class of which Corbett wrote—a ship type that by definition is supposed to be cheap and plentiful in numbers. The mismatch between cost and the return on investment would be daunting. The ROI just wouldn’t be there for a scouting, command-and-control, and show-the-flag vessel.

Who pays $13 billion for a fleet auxiliary—a warship that sits out the main fight?

Are there any remedies for what ails the aircraft carrier? Potentially. It feels as though the U.S. sea services stand at an awkward moment. New technologies could start paying off before long, but it remains unclear whether and when they will fulfill their promise. Choice matters as well. Service chieftains need to choose the right systems to accomplish their purposes, and they must persuade Congress to fund new tech in sufficient mass to make a difference at sea. Mariners need to learn to use new hardware and software for tactical and operational advantage. Directed-energy defenses have made strides, for example, as have electronic warfare, uncrewed tankers meant to extend the reach of the carrier air wing, and longer-range, speedier antiship missiles. Taken together such innovations could harden the carrier’s defenses against attack while making it a rangier, heavier-hitting offensive platform.