WASHINGTON: The seas are shrinking. As missiles grow longer-ranged and more precise, as sensors grow ever sharper, there are ever fewer places for a ship to hide. “A ship’s a fool to fight a fort,” goes an old naval adage, because a land base can carry more ammunition and armor than anything that floats. Admirals have always been uneasy about bringing their fleets in range of shore-based weapons. But what does the US Navy do when those weapons can find you hundreds or thousands of miles out to sea?

That’s the question posed by Andrew Krepinevich in his forthcoming study, Maritime Competition In A Mature Precision-Strike Regime. (Krepinevich gave Breaking Defense an exclusive advance copy and answered our questions about it at length). The thinktank Krepinevich heads, the Center for Strategic and Budgetary Assessments, has long led the way on the concepts called anti-access/area denial (A2/AD) and Air-Sea Battle, which wrestle with the rising power of China and other countries to keep US forces at a distance. His new study carries this earlier work to its logical conclusion: a world in which both sides have built the wide-area network of spy satellites, drones, bombers, and missiles that is currently a US monopoly — the “mature precision-strike regime” of the title.

It’s a world in which naval warfare is very different — indeed, in which land-based forces can do so much damage to fleets that the conflict isn’t purely “naval” anymore. (That’s why the study uses “maritime” instead). The World War II parallel is not Midway, where US and Japanese carriers struggled to find each other in the vast Pacific: It’s the Mediterranean, where both Axis and Allied ships were easily found and ravaged by land-based bombers. The difference is that modern technology effectively shrinks the Pacific to the size of the Mediterranean.

“In the Med [in World War II], you have these no man’s lands where it becomes very difficult to operate on the surface of the water,” Krepinevich told me. “In a mature [precision strike] regime, the oceans may shrink to Mediterranean size.”

Krepinevich foresees the anti-access/area denial zones of CSBA’s earlier studies expanding ever further into the ocean until they meet in the middle, creating a no man’s land — or rather, no man’s sea — where both sides venture only at grave peril. After centuries in which freedom of maneuver was the norm in naval operations, much of the ocean would be carved up into impassable killing fields. In cases where rival countries are close together, as Japan, South Korea, and Taiwan are to China, the Gulf emirates to Iran, or the Baltic States to Russia, the entire territory of the smaller nation may be inside the no-go zone. This means US allies would be blockaded, under bombardment, and under siege from the second that the shooting started. It also means US forces coming to their rescue would have to cross the oceanic equivalent of World War I’s Western Front.

“If you have to reinforce Taiwan or some critical point,” said Krepinevich, “and you don’t have a lot of time to prepare the battlefield, you are confronted with the prospect of ceding that key interest or suffering high levels of attrition.”

So how do you cross the killing fields intact? Just like the commanders of World War I, who turned to various combinations of new technologies (British tanks) and tactics (German stormtroopers), Krepinevich looks at a range of possibilities.

The simplest solution is not to go in at all. Instead, blockade the enemy and try to force him to come out into your kill zone to break the siege. The tricky part, of course, is getting the enemy to cooperate. Such a distant blockade, keeping China’s exports from reaching buyers and keeping Mideast oil from reaching China, is the heart of the “Offshore Control” strategy proposed by retired Marine colonel T.X. Hammes as an alternative to Air-Sea Battle. That’s an attractive option when you have time, Krepinevich told me. But our allies trapped inside the enemy’s kill zone (e.g. Japan) might not last long enough for our distant blockade to win the war.

On the other hand, if we take a more aggressive course, our own ammo may not last long enough. Fighting a high-tech enemy would eat up missiles, drones, and even manned systems — with the loss of human life that entails — at a rate far higher than relatively defenseless targets in Libya, Afghanistan, or the Islamic State. US commanders are already lamenting their low stockpiles of precision weapons, and US industry can’t churn out new ones very fast.

“In a prospective near-term conflict with the People’s Republic of China, we have little ability to surge production of munitions, let alone major platforms,” Krepinevich said. “So if you are the PRC, you may only need to plan to maintain a few months’ supply of oil. If you are Beijing and thinking long-term, you can stockpile — which I understand they are — or build underground pipelines on land,” for example to oil-rich Russia.

Stockpiling oil, however, is much easier than stockpiling precision-guided weapons. If China and other adversaries can make us run out of ammo, why can’t we make them run out of theirs? In the age of iPhones, the technology to make missiles smart keeps getting cheaper, Krepinevich said, but the technology to make them long-ranged does not. That means even a major power will have a limited number of its most dangerous weapons.

One way of depleting the enemy arsenal is to make them shoot at nothing: decoys, electronic warfare, and even hacking the enemy’s network can all create illusory targets. When the enemy does fire at something real, however, it would be great to be able to shoot the incoming missile down. That’s a problem with current missile defenses, which rely on high-priced interceptors ships can only carry in small numbers. Laser weapons or electromagnetic rail guns, however, could keep taking cheap shots until the enemy is out of expensive missiles.

Long-range missiles aren’t the only limited resource: So are the long-range sensors that find the targets in the first place. Satellites are increasingly vulnerable to both direct attack — lasers blinding their sensors, for example — and indirect attack — hackers compromising their downlinks to earth or smart bombs destroying the ground control stations. As space goes dark, the warring powers will probably resort to high-altitude drones for both reconnaissance and communications relays, Krepinevich says. But those drones need to be smart enough to operate with a high level of autonomy, he added, or the long-range data links between them and their operators will become another major vulnerability to be jammed and hacked.

Overall, the wireless network connecting the far-flung enemy forces — both human and robotic — will be a vital target. Cyber espionage could play as vital a role as cracking Nazi and Japanese codes (the ULTRA and MAGIC projects) did in World War II. Cyber attack could also introduce false data or shut down key enemy systems at a critical time. But this domain of warfare is even more filled with uncertainties than the rest of the future, Krepinevich cautioned.

“To a certain extent, cyber to this regime is kind of like airpower in the ’20s and ’30s,” he said, “where everybody knew it was going to be important,” but they didn’t know how important or in what way.

With airpower, however, at least the uncertainty largely ended once the shooting began: You could see planes going down, the cities in flames. With cyber warfare and electronic deception, however, both attack and effects are largely invisible. If the enemy stops shooting long-range missiles at you, he may have run out, he may have been blinded by your cyber and electronic attacks — or he may be holding his fire for when you come closer, into his trap.

Eventually, though, US forces will have to come closer, if only because they’re running out of long-range weapons. So what kind of future force will best survive the 21st century no man’s land? Stealth will still matter, Krepinevich predicts, albeit continually challenged by ever more sensitive sensors backed by big data analytics. Submarines and land-based bombers — larger and longer-ranged than any carrier aircraft — will likely form the leading edge of the force, backstopped by land-based long-range missiles.

That said, Krepinevich hardly rules out a role for surface ships, even ones that present as big a target as an aircraft carrier. While they’re more visible and vulnerable than submarines, surface ships also cost much less per pound of payload, potentially giving them much more firepower. The critical question is what that payload is. Currently, he warns, potential adversaries have cruise missiles that can hit a US carrier from ranges so long the carrier’s aircraft can’t strike back. (That is, not without mid-air refueling, a prohibitively risky maneuver in hostile airspace). Longer-ranged carrier aircraft — not necessarily manned ones — could keep the Navy’s favorite flagships relevant.

In fact, Krepinevich notes, most military revolutions begin on the margin, with a few cutting-edge systems in an otherwise traditional force, if only because that’s all most militaries can afford. The German army of the blitzkrieg had more horse-drawn carts than tanks. The US Navy of December 7, 1941 had more battleships than aircraft carriers — and the battleships that survived, refitted with extra anti-aircraft guns, played an important supporting role in the carrier war that followed. A relatively small amount of new technology, applied using new tactics, can make a decisive difference for a large force. The trick, of course, is figuring out what the right new technologies and tactics are.

That’s the discussion Krepinevich hopes to help start.

“This is really version 1.0,” he said of his report. “This is a best first guess, and it’s based on trends,” he said, but there are a tremendous number of variables in play, more so perhaps than any previous time in military history. Nevertheless, he went on, “it’s better to have something like this, that provides that point of departure, than to have nothing at all and just keep stumbling toward the future.”

“It’s the beginning of the conversation,” Krepinevich said. “It’s not the end.”