If you aren’t new to these pages you probably already appreciate the centrality of naval power in the policy tensor’s framework for understanding world affairs. The primacy of naval power is due to the fact that the world is made up of large landmasses separated by large bodies of water, so that the plumbing of global capitalism is necessarily maritime. Whereas the ‘global balance of power’ is determined regionally by land-based military power, the maritime realm is a natural monopoly. It is this latter fact that centers the international system. Merchant oligarchs flock to the dominant maritime state for protection. It is the job of the “central government” to undertake system-wide tasks, organize politico-military action at the global level, and ensure the smooth functioning of global capitalism.

The maritime realm is a natural monopoly for two reasons. First, the existence of natural control points allows the dominant state that garrisons them to bottle-up rival navies, deny rivals access to world markets, and monopolize intercontinental politico-military interactions. This is especially important in peacetime, when the field-guns on land are largely silent. There is a reason why international coercion is called ‘gunship diplomacy.’ Basically, the army is a very blunt instrument of power. It is maritime power that is the instrument best suited for international coercion. Second, Mahan was right all along in arguing that contests for naval supremacy are settled by decisions reached in great battles between the major battle fleets of opposing navies. The balance of naval power is determined by the most formidable ships of the contestants. The side fielding superior firepower prevails almost surely because there is nowhere to hide at sea. Like squash, small differences in capabilities yield largely one-sided decisions. Whereas an army two-thirds as strong as the opponent can very well draw the adversary to a stalemate (like France in 1914), a navy two-thirds as strong as the adversary can barely hope to survive in one piece. Moreover, naval battles are short affairs. In 1904, the Japanese fleet sunk the entire Russian fleet in a single day’s action. In World War I, Germany’s “risk fleet” remained bottled-up in the North Sea for the entire duration of the war. The only major naval engagement of the war—the Battle of Jutland—failed to yield a conclusive decision; proving to be a major disappointment to British Admirals who were fully expecting to crush the German fleet there and then. Similarly, the war in the Pacific was decided largely at Midway when the Americans sunk four Japanese aircraft carriers.

The balance of naval power, then, is a question of the relative strengths of the major battle-fleets of the adversaries. And the strength of a state’s fleet is determined overwhelmingly by the number of capital ships it can field. Capital ships are those warships that can put up a fight against the most formidable ships of the time. As usual, this is largely a question of firepower and armor. In the two-and-a-half millennia preceding the advent of ocean-going sailing ships, the galley was the only game in town. The Phoenicians, the Carthaginians, the Athenians, the Persians, the Romans, the Ottomans, and the Venetians imposed navel hegemony in the Mediterranean Sea by means of fighting ships powered by human muscle. The tactic was always the same: sink the adversary’s vessel by ramming it from the side, and/or “parallel park” next to the adversary’s vessel and board it to settle the contest by sword, spear, and/or firearms. Even after the arrival of gunpowder, the tactics changed only marginally. Hardly any ships were sunk by broadsides from galleys until the late fifteenth century. That is to say, the beginning of the long sixteenth century (1450-1650).

The simultaneous emergence of sail and sea-borne artillery changed the nature of the game for good. The King of Portugal (unlike elsewhere in Europe, private merchants hardly played any role) began exploring the Atlantic seaboard off Africa early in the fifteenth century. The Portuguese navy pioneered cannon bearing ocean-going ships powered by sail. Innovations in navigation (the astrolabe, marine cartography), sailing (multi-mast ships and multiple sails per masts), and gunnery (lighter and safer bronze artillery) coupled with an intense desire to seek an alternative route to the Indies propelled the Portuguese sailors further and further south along the long African coast. They rediscovered the southern route to the Indies in 1488. Soon after, they replicated the 2000-year-old Phoenician feat of circumnavigating Africa. By the close of the century, the Portuguese had a formidable ocean-going navy that had no counterpart in the world. The 100-ton caravels that were used in the initial explorations gave way to the 500-ton carracks, which in turn gave way to huge naus, “the Great Ships” sometimes displacing a thousand tons, and finally, the galleons.

The nau, while it was equipped with guns, was primarily a cargo ship; while the galleon—with its superior speed, firepower, and maneuverability—was a true capital ship (even though it too carried cargo). In some sense, the Age of Sail (1490-1860) is synonymous with the galleon—the beautiful design was to dominate the oceans for three centuries. But it was the Great Ships that led the way in the Age of Exploration. The Portuguese set up many factories in India where most of the Great Ships that were used in the Indian Ocean were made. The decisive naval battle that marks the modern era apart took place at Diu in 1509. (This marks the modern era apart because the Portuguese succeeded in supplanting the centuries old Levant route for the pepper trade. To use the plumbing analogy, the southern route became the primary “pipe” connecting Europe to Asia.)  A small Portuguese fleet of just nine Great Ships obliterated the joint fleet of the Mumlûk Sultanate of Egypt and the Sultan of Gujarat which sported a hundred dhows (a generic name for the small sailboats that were a staple of the Indian Ocean trade; many can still be seen plying the routes today). The latter had the support of the Venetians and the Ottomans whose joint stranglehold of the pepper trade the Portuguese had sought to break. Already by this point though, even the formidable Venetian fleet in the Eastern Mediterranean was absolutely uncompetitive against the Portuguese warships. Luckily for the Venetians, the Portuguese never ventured up past the Red Sea.

What came next was not a radical new ship design; it was a conceptual innovation. By the late sixteenth century, the Spanish, the English, the French, and the Dutch had all acquired armed sailing ships. These were overwhelmingly private. No one other than the Portuguese had a state navy worth speaking of. For instance, the “invincible armada” sent by the King of Spain to invade England that met its fate at the hands of the Anglo-Dutch fleet in 1588 was mostly made up of leased private ships. Even the Dutch, who prevailed against the might of Spain and emerged supreme in 1609, were barely organized. Naval battles were still mêlées—with individual ships firing and maneuvering at will with no order of battle; fighting in whatever arrangement they found themselves in. The potential firepower of sea borne artillery was finally unlocked during the Anglo-Dutch naval wars (1654-1656, 1665-1667, 1672-1674), when both sides increasingly followed the ‘line of battle’ with heavily armed gunships arranged in one file to allow the full fury of their artillery to be brought to bear on the adversary. Specifically, it was the second Anglo-Dutch war (wherein the Dutch prevailed handsomely over their inferiors) that marks the final victory of this concept. During the first war, it was used inconsistently and mostly by England. This was one reason why the English “won”; the other being the actual existence of a “national” navy. During the third war—the one where the Dutch took on the combined might of England and France—the state navy of the Dutch Republic itself remained grounded.

The ‘ships of the line’ were to remain the capital ships until the arrival of steam power and armor on the high seas in the mid-nineteenth century (reigning from 1660-1860). While the Dutch may have adopted ships of the line at the end of their reign at the summit of world affairs, it was England that really mastered the technique. The Royal Navy had emerged as a formidable force during the English Civil War (ironically, siding with Parliament). By mid-century, it had become an effective instrument of national policy. The fight against the Dutch had led to a series of institutional innovations such as the “Fighting Instructions” and a permanent staff. By the end of the War of Spanish Succession in 1715, England emerged with a preponderance in naval power. The Royal navy commanded 124 ships of the line; more than all the other powers combined. Of course, capabilities alone aren’t sufficient. It took nearly another half-century for England to secure control of the world’s sea lanes. It was only at the end of the Seven Years’ War (1756-1763), that the question of who will succeed the Dutch was finally settled. Even though England lost the War of the American Revolution (1775-1783), she maintained a firm grip on the maritime realm. The wars of the French Revolution (1792-1802) and the Wars of Napoleon (1803-1815) only confirmed what was already clear: no one could challenge the Albion at sea.

The ships of the line were dethroned with the arrival of the ironclads in 1858-1860. Armored and powered by steam, the ironclads almost immediately made sailing ships—that had dominated the high seas since at least 1490—obsolete. It was not that the ironclads were per se superior to the sailing warships. It was the advent of the exploding shell that made wooden hulls simply uncompetitive. More generally, the industrial revolution had changed the naval game permanently: from now on, the balance of naval power came to depend on industrial strength. The ironclad era (1860-1910) was one of constant innovation. As the century matured, the armor became thicker, the displacement larger, and the guns bigger and more numerous. Capital ships became more and more expensive. British naval mastery for the rest of the century rested on the firm foundations of her industrial strength, her unrivaled financial resources, and a virtual monopoly of stoking coal. By the close of the century however, seemingly out of nowhere, naval competitors of an entirely new magnitude had arrived on the world stage.

Germany, Japan, and the United States embarked on naval expansions at the turn of the century, following on the heels of France and Russia. The story is an old one on these pages by now, but these developments forced Britain’s hand in two ways. First, she realized that competing with the American Republic was the surest path to financial ruin, and therefore decided to surrender naval mastery in the Western Hemisphere (1901). Likewise, the naval expansion of the continental powers (France, Russia, and Germany) forced her to forge an alliance with Japan (1902); whereby she effectively ceded Asian waters to Japan. Second, the Royal Navy, under the far-sighted stewardship of the First Sea Lord, Sir Admiral Fisher, decided to raise the stakes. Fisher decided on the production of new capital ships of almost imponderable power. The HMS Dreadnaught, commissioned in 1906, was not simply an ironclad. It was such a decisive break that earlier designs are now referred to as pre-Dreadnaughts. The HMS Dreadnaught featured steam turbine propulsion; 11-inch Krupp cemented armor (German, obviously); 12-inch guns that delivered hitherto unheard of firepower; an unprecedented speed of 21 knots; and a displacement of 20,000 tons. No other warship in any fleet could even begin to compete with the Dreadnaughts (the name immediately given to warships in the same class as the HMS Dreadnaught). The Americans, the Japanese, the Germans, the French, the Russians, and the Italians, as indeed the British themselves, all suffered a massive capital loss as their standing fleets became irrevocably redundant.

There being no choice, the other powers tried to catch up as soon as possible. The newer, richer arrivals—the Germans, the Japanese, and the Americans—were somewhat quicker to catch up. However, the British went into World War I with a formidable lead in capital ships—by 1910, only Dreadnaughts counted in the balance of naval power. In the aftermath of World War I, the victorious allies agreed to a strategic arms limitation with the Washington Treaty of 1922, that put a moratorium on the construction of more capital ships and limited their ratio to 5:5:3 between the United States, Great Britain, and Japan. The treaty was renewed in 1930, and again in 1934, despite Japanese protests. In 1935, Japan simply walked out and launched a major naval armament program. Around the same time, Germany decided to build powerful battleships (including the Bismarck, the most powerful battleship ever built) and a fleet of submarines.

But at the beginning of World War II, the Dreadnaught era (1910-1940) had already come to an end. As usual, previous technology was no longer militarily competitive. Once the aircraft carrier had arrived, flying artillery made warships obsolete. The guns on the battleships couldn’t move fast enough to target the aircraft, while the ships themselves were sitting ducks to the flying cannons. Capital ships were now aircraft carriers. The era of the aircraft carrier was suitably inaugurated on the day that still somehow manages to live “in infamy.” The spectacularly successful attack on the American fleet at Pearl Harbor was, in fact, a blessing in disguise. For the attack largely destroyed America’s fleet of obsolete battleships, allowing her to forge a brand new fleet of aircraft carriers ex nihilo. The Pacific War was decided in the air over Midway. The balance of naval power had become the balance of air-sea power.

Submarines had played a secondary role in the world wars: they were deployed to harass commercial traffic, never to contest command of the seas. Ironically, their most significant contribution was to draw America into the war. During the Cold War, they became the primary carrier of the superpowers’ nuclear deterrent. By the 1970s, the majority of intercontinental ballistic missiles tipped with nuclear warheads were sea based. The inherent stealth of the nuclear-powered submarines, and their unlimited range (restricted only by the need to replenish the crew’s food supply), made them much more suited for ensuring a second-strike capability than land based silos. The United States relied on its fleet of nuclear submarines even more than the Soviet Union.

With the collapse of the Soviet Union and the dawn of the unipolar world, the United States has enhanced its power projection capability both on the high seas and from the high seas. The ability to strike targets far inland from sea borne platforms has increased steadily with the range and striking power of modern aircraft and missiles. Nimitz Class nuclear-powered aircraft carriers are the most formidable instruments of power projection ever made. But the spread of long-range precision strike weaponry is already beginning to undermine the supremacy of the aircraft carriers. To put it simply, hypersonic cruise missiles tipped with tactical nuclear devices can take out any aircraft carrier within a thousand nautical miles (the missile needs to be hypersonic to avoid getting shot down by theater missile defenses such as Israel’s Iron Dome). Even with a conventional warhead, a long range anti-ship cruise missile can down even the biggest ships with high probability. Indeed, the United States Navy is itself developing such a weapon.

And the problem is only going to get worse from here on. There is nothing very complicated about long-range precision strike; certainly nothing that cannot be mastered by the Chinese in a couple of decades. It is hard to see how aircraft carriers can maintain their capital ship status for very long at all. Basically, the aircraft carriers are floating dinosaurs. They will be relegated to secondary theaters (where no advanced adversary can threaten them) even before the missiles start to fly. But this does not mean that America’s naval primacy is at an end. The United States has a very neat trick up its sleeve. What the Americans have quietly decided (so quiet that even someone as obsessed as me didn’t realize it until recently) is to bet on a new Virginia Class of nuclear-powered fast-attack submarines armed to the teeth with advanced cruise missiles that can take out other submarines, surface ships, aircraft, and targets deep inside the adversary’s mainland. These boats—submarines are called boats—can operate both in littoral waters near an adversary’s coastline and in the deep ocean. They are the quietest and stealthiest submarines ever built. Equipped with life-of-the-ship reactor core—no refueling needed for thirty years—they have unparalleled endurance and unlimited range. They have the most sophisticated array of sonar and eavesdropping sensors and even a lock-out chamber for inserting special operators ashore.

The Virginia class is America’s answer the proliferation of long-range precision strike weapons to what the Pentagon calls America’s “near peers” (Russia and China). It is the new capital ship of the twenty-first century. The US navy plans to build at least fifty of these stealthy attack platforms. This would certainly go a long way towards solving the dilemma posed by China’s growing anti-access, area-denial capabilities in waters close to the Chinese mainland. The enthusiasm for these plans is very high in the beltway. These developments pose a very tricky problem however. America’s adversaries are likely to develop capabilities to try to counter these attack platforms. They will certainly invest in surveillance and detection capabilities, and develop specialized submarine hunters (perhaps suicidal unmanned underwater vehicles). Since America’s nuclear deterrent is also carried by nuclear-powered submarines, the adversary will have no way of distinguishing between the two. What looks like a theater operation in a limited conflict to the adversary will appear as a counter-force strike to the Americans (that is, a strike against their nuclear deterrent). The indistinguishably of the two platforms therefore undermines crisis stability (whether or not a crisis leads to an escalation to the highest level), thereby significantly increasing the likelihood of inadvertent global thermonuclear war.