Keys to the World

The ocean-going ship​ has been one of the principal engines of history. Breakthroughs in hull, mast and rudder design, not to mention navigation techniques, led to the galleon and so to the early European maritime empires. Since at least the 15th century naval strength has been a central component of national power. Sea power isn’t just a matter of building a bigger navy. Nor is it reducible to the skill of admirals. Even the best ships with the ablest captains will struggle without conveniently located ports and the infrastructure they provide. Without secure access to the relevant seas a large navy is just a lot of metal to clean. The best summation of the importance of naval position was given in 1904 by the British admiral John Fisher: ‘Five keys lock up the world! Singapore, the Cape, Alexandria, Gibraltar, Dover. These five keys belong to England.’ But if you leave strategic bases aside, it is often the show of naval force, rather than its application, that has proved most potent.

The modern tool of naval power projection is the aircraft carrier. The biggest of them, which belong to the US Navy, are 333 metres end to end (longer than the Shard would be if it were laid horizontal) and displace 100,000 tonnes of water with their bulk. They rarely travel alone. An aircraft carrier is usually escorted by cruisers, destroyers and submarines, as well as fighter jets, attack aircraft and helicopters. US carriers are nuclear-powered so don’t need regular deliveries of fuel. Naval enthusiasts tend to take emphatic pride in their nation’s carriers: the Royal Navy refers to HMS Queen Elizabeth, launched in 2014, as ‘4.5 acres of floating sovereign power’. The US has eleven full-size fleet carriers, more than the rest of the world combined. It wasn’t always so. Japan had ten carriers by 1940 and Japanese admirals pioneered the carrier group, before the US sank almost all of them in the Pacific. In a sense American aircraft carriers are throwbacks: relics of the military-industrial production of the Second World War, when US shipyards built thousands of warships. The point of them today is to transfer the advantages of military power far out of sight of land, beyond the range of strategic ports, bestowing on their masters the power to set the rules at sea.

Because most countries have coasts and around 80 per cent of physical trade depends on the seas, the question of who governs them is critical to international relations in general. The balance of sea power matters to everyone, most of all to large island countries (New Zealand, the United Kingdom, Madagascar) and archipelagic states (Indonesia, Japan, Malaysia, the Philippines). David Bosco opens his account of ocean governance with the question of the Senkaku Islands, eight uninhabited rocks between Taiwan and Okinawa which are in themselves no good to anyone but are nonetheless bitterly contested. Under US occupation from 1945, when the islands were sometimes used as a bombing range, the Senkakus were given over to Japan in 1972. They are still subject to territorial claims by China and Taiwan. Islands that lie between major powers have always been a good pretext for national disputes, but there are also practical reasons for wanting them. Most states struggle to assert claims to the seas far beyond their own shorelines, and the possession of islands, even islets like the Senkakus, may allow for a better claim to what would otherwise be treated as open ocean.

The seas have often been thought of as ‘lawless’. But Bosco, who has an American law school background, contends that an international legal regime for the oceans has been in place for at least two centuries. Iberian, Dutch, French, and then Anglo-American maritime empires usually favoured a Grotian ‘freedom of the seas’, which in practice often meant their freedom to conquer by sail. European powers adopted a lofty language of the global commons while insisting on retaining advantages for themselves. Britain perfected the practice after the Napoleonic Wars, and the US continued where Royal Navy admirals left off. Franklin Roosevelt said it best: ‘All freedom – meaning freedom to live, and not freedom to conquer and subjugate other peoples – depends on freedom of the seas. All of American history – North, Central and South American history – has been inevitably tied up with those words, “freedom of the seas”.’ Bosco is concerned that the idea of that freedom is vanishing. Russia is planting flags on the bottom of the Atlantic, China is harassing fishermen in the South China Sea, and Turkey and India are making maritime territorial claims based on arguments about continental shelves. It isn’t a coincidence that the upstarts all sit outside areas of US hegemony and the traditions from which it drew. ‘If open conflict does break out in Asia,’ Bosco says, ‘it is likely that “freedom of the seas” will be a battle cry.’

The doctrine of free seas has some predecessors in the ancient world. The extent of Roman influence around the Mediterranean necessitated freedom of access – for Romans. One forerunner of modern maritime codes was seventh-century Byzantium’s Rhodian Sea Law, which dealt with liability for lost or damaged cargo. The 12th-century Rolls of Oléron provided indemnity for captains whose sailors got drunk in port and injured people in fights. But it was difficult for navies to lay down the law in the ocean expanse until the development of better naval weaponry. Bosco implies that ships had a limited ability to engage one another at sea until the end of the Age of Sail. This underestimates the trireme ram, Korea’s armoured Geobukseon and the innovations of the Portuguese navy. It also misplaces the introduction of naval artillery by almost three hundred years, making nonsense of the 1588 Battle of Gravelines, the defeat inflicted by England on the Spanish Armada, achieved with the use of naval cannon.

As soon as there were global maritime empires there were attempts to claim ocean territory, or at least the land found while exploring it. The Treaty of Tordesillas (1494) and the Treaty of Zaragoza (1529) divided the Atlantic and then the Pacific into Portuguese and Spanish domains. Anglo-Dutch competition led to the 17th-century argument between Hugo Grotius, the Dutch jurist who saw the seas as global commons, and the English lawyer John Selden, who argued for a right to claim territory close to the mainland. Mare liberum or Mare clausum? Writing in the early 18th century the Dutch legal theorist Cornelius van Bynkershoek provided a synthesis of sorts in the cannon shot rule, which declared that states could claim the seas ‘as far as cannon will carry’ from the shoreline. At the time that meant around three miles, which happens to be approximately the distance of the horizon as seen at sea level. The three-mile rule, with freedom of the seas beyond, suited Britain when it became the principal naval power from the mid-18th century onwards, and Admiralty charts were closely guarded assets until the British felt comfortable enough in their navigational advantage to start selling their maps for good fees in the 1820s. In 1841 Britain asserted dominion over Hong Kong and twelve years later Matthew Perry steamed into Edo. This is what was meant by freedom.

Bosco’s book, with its legal slant, doesn’t really explain how Anglo-American maritime dominance came about. In the late 16th century, John Hawkins, a privateer who became treasurer of the British navy, transformed what was primarily a coastal defence force into an ocean-going fleet capable of plundering Iberian colonial trade. But it was the English Civil War that provided impetus for the creation of a large professional navy at the service of the state. As the result of a remarkable shipbuilding effort the navy doubled in size between 1649 and 1651. It was immediately put to work against the Dutch and in a bout of colonial expansion in the Caribbean. At the turn of the 18th century the British and French navies were roughly equivalent in size. By its end, Britain had five hundred ships to France’s two hundred. In 1759, at the Battle of Quiberon Bay, Britain inflicted a major defeat on the French navy that set up its victory in the Seven Years’ War. By the time the two powers relitigated the matter during the Napoleonic Wars Britain’s advantage was too great. Trafalgar made the decision final.

British naval dominance was always accompanied by rhetorical flourishes about freedom of the seas. Yet it was Britain’s control of the Atlantic that made it possible for its merchant ships to transport more than three million slaves to the Americas. Under the Slave Trade Act of 1807, abolition became a pretext for boarding foreign ships anywhere at sea. After US independence the British navy intercepted supply ships in the Atlantic, which in 1780 provoked the anti-British League of Armed Neutrality between the northern European naval powers and then the war of 1812. The interceptions represented no more than a shift from the traditional British practice of authorised privateering, as effected since the days of Francis Drake, to the state carrying out piracy on its own account. While Britain was bombarding North African towns in response to the wrong kind of (Barbary) piracy in the 18th and 19th centuries, its leaders adopted ever more vaulted commitments to free seas. And British sea power had never been greater. The requirement that foreign ships salute when passing through the channel had been magnanimously dropped after the Battle of Trafalgar: why limit symbolic deference to the channel? Britain was to be what the diplomat Eyre Crowe later, ominously, called ‘the neighbour of every country accessible by sea’.

Britain remained unchallenged as the pre-eminent naval power until the onset of the First World War. When towards the end of the 19th century the German Empire mounted a challenge by building a navy, acquiring overseas colonies, and establishing a coaling station in the Zhoushan Islands at the mouth of the Yangtse, it proved to be a grave strategic mistake. Bosco has very little to say about the effects of the war. Referring to the British naval blockade of Europe he asks why it was that ‘the edifice of norms protecting freedom of navigation’ was allowed to crumble. The answer couldn’t be simpler: the world was at war. But Bosco reduces it to ‘British and German restrictions on free navigation’. His treatment of the interwar period, and the arms race that dominated it, is also lacking. The 1922 Washington naval conference and its successor in London in 1930 gave Britain and the US 30 per cent of global naval tonnage, and a far greater advantage in destroyers and other smaller ships. Britain and the US dictated the sizes of ship that other states were allowed to build. There were limits on the size of submarines and the kinds of weapon they were allowed to carry. At the Washington and London conferences, the US and UK froze the global balance of naval power in their favour. The major powers effectively stopped building battleships until 1936. Because warships take a long time to build, the balance set in 1922 was still in effect in 1939: a remarkable feat for Anglo-America.

Bosco mostly leaves out the Second World War, skipping straight from 1939 to the Truman proclamations of 1945. The US emerged with total dominance on the seas and in the air. The Soviet Union didn’t really become a naval power until the 1960s and never rivalled the US on water. Truman asserted exclusive rights to continental shelf waters, while still claiming to uphold freedom of the seas. Other states in the western hemisphere, from Mexico to Chile, made similar claims to continental shelf waters. The USSR followed suit, extending its territorial waters to twelve miles from the coast. In 1970 Brazil declared a two-hundred-mile territorial sea. States were playing by the new rules the US had ushered in. But the idea of freedom of the seas was too useful to be jettisoned. Whenever it was convenient, the US opposed the territorial claims of other countries on the basis of commitment to free commons. When in the early 1970s Canada tried to impose environmental controls on shipping in the North-West Passage, the US State Department’s executive secretary Ted Eliot said it was unacceptable that a neighbour ‘feels it can undertake such action in the face of United States opposition’. The US Navy blockaded Guatemala and intercepted ships in the Taiwan Strait. But maritime freedoms were regarded rather differently by small states that had experienced the dangers the seas could bring to their shores. Freedom of the seas, Peruvian officials argued, meant ‘colonial subjugation’.

In​ 1948 the UN established the International Maritime Organisation to deal with the great expansion in merchandise trade, which became more urgent with the rise of containerisation in the late 1950s. The logistics and regulation of global shipping became a central fact of industrial capitalism. But deciding who was responsible for enforcing laws at sea was made more complex by the use of flags of convenience. Since 1927, thanks to a ruling by the Permanent Court of International Justice, ships have been subject to the laws of the state of whichever flag they fly. As a result companies found it useful to register their ships in Liberia, Panama or the Marshall Islands: anywhere with open registries. Panama was attractive to US shipowners because of the convenience of the canal and because its currency was pegged to the dollar, but especially because its safety regulations were lax. By 1970 flags of convenience were flown on a quarter of merchant ships by total tonnage. Sometimes they had immediate practical value: during the Iran-Iraq war, the US allowed Kuwaiti oil tankers to fly American flags for their protection. But for the most part they were an instrument of labour subjugation: foreign laws made it easier to screw over sailors. France and the Soviet Union mounted campaigns against the practice but the US overruled them.

In the 1970s momentum began to build at the UN for a multilateral treaty on the laws of the sea. Bosco provides an entertaining account of the Maltese diplomat Arvid Pardo’s efforts in that direction, inspired by hallucinogenic visions for undersea development including fish farms staffed by dolphins. Pardo was instrumental in beginning the nine-year drafting process that produced the 1982 UN Convention on the Law of the Sea. Unlike early efforts at a maritime convention, this was a full treaty. Flags of convenience would continue to be permitted. States would have the right to claim up to twelve miles of sea as sovereign territory, overthrowing the three-mile cannon shot rule favoured by Britain.

The convention also introduced Exclusive Economic Zones as a way of mediating the areas between national waters and the high seas. An EEZ could stretch as far as two hundred miles from the coast, allowing even small islands to make great claims. Coastal states could assert rights to the hydrocarbons and fish in their zones. But in practice the EEZ was a troublesome concept: states tend to interpret their zones as their own territorial possessions but object when their adversaries do the same. Another principle the convention codified was the right of ‘innocent passage’ in the territorial waters of other states. The arrangement was to the US’s advantage, but American nationalists were opposed in principle to the idea that the US should be subject to international rules. So the US ended up voting against the convention while also declaring its own EEZ covering seven million square miles. The convention didn’t come into effect until 1994 and the US still hasn’t ratified it, though it recognises its provisions when they accord with its interests. Hundreds of EEZs have since blossomed. Ultimately the convention allowed commercialised enclosure by all without infringing on the control of the commons exercised by the US.

The conventions and legal disputation Bosco is interested in are only so much marginalia when set beside the brute fact of US naval hegemony. Paul Kennedy’s account of the naval history of the Second World War makes this clear. For Kennedy the main story of the war at sea is the ascent of the US, having started out as one naval power among many, to ‘naval mastery at the close of the war years’. In 1939 there were six major powers at sea: the Royal Navy, the US Navy, the Imperial Japanese Navy, France’s La Royale, Italy’s Regia Marina and Germany’s Kriegsmarine. The British fleet was the only truly global navy, ranging from Jamaica to Sydney. Having many colonies to police, Britain naturally favoured light cruisers for the work of maritime empire. German and Italian admirals favoured heavier ships for battles closer to home. Early in the war the Royal Navy struggled to compete with its Italian and German equivalents, but the Italian part of the alliance eventually collapsed thanks to its inferior ships and submarines. Germany’s submarines were more advanced but it had too few of them, no more than fifty in the first year of the war. (Contrary to the usual narrative, Italy ended up sinking more British submarines than Germany did.) Following a strategy put forward by Wolfgang Wegener in his book Die Seestrategie des Weltkrieges (1929), which argued that Germany could not break a Royal Navy blockade in the North Sea directly, the Kriegsmarine focused on a campaign to seize Norway and break out of the North Sea through Norwegian harbours.

Germany took Norway in 1940, but at the cost of much of its navy. Wegener hadn’t foreseen how vulnerable ships would become. Air attacks and torpedoes neutered the German surface fleet within the first two years of the war, and German submarines were able to sink British battleships. Without air cover large surface ships were sitting ducks that could be sunk with a single torpedo. Between November and December 1941, the Royal Navy lost six capital ships, four of them to submarines. The war demonstrated the redundancy of the battleship and the value of destroyers and escorts. Allied supply transports continued to be under serious threat from the Kriegsmarine until the adoption of small centimetric radar and air escorts. But the central contest of the war, between the Soviet Union and Germany, put limits on German submarine production. Despite the pleas of Admiral Dönitz, Germany wasn’t able to build large numbers of submarines until well into 1942. By then, technical innovations in anti-submarine warfare were turning against them, definitively so after the deployment of the acoustic torpedo in March 1943.

In keeping with the traditions of Anglosphere scholarship, Kennedy makes too much of the contribution of British and American actions in the Atlantic to the Soviet victory over Germany. Raw materials and equipment (especially Western trucks) supplied by sea were helpful to the war effort, but much of the Lend-Lease aid arrived after the great battles of 1941 and 1942. The importance of efficient, domestic Soviet arms production cannot be overstated. The Soviet Union would have won regardless of the sideshow in the Atlantic. But the Pacific War was a different matter. The British assault on the Italian fleet in Taranto had demonstrated what aircraft carriers could do. More dramatic was Japan’s aerial attack on HMS Prince of Wales and HMS Repulse, which showed that surface battleships were useless against modern aircraft and good torpedoes. Britain realised it couldn’t hold the empire’s eastern possessions against sustained pressure. The Imperial Japanese Navy was professional and well equipped. Japan had a fine war record up until 1942; it had conquered a great deal of territory. It had the best fighter aircraft and the best torpedoes. In the Kidō Butai it had a carrier fleet. But it was completely overwhelmed by the US Navy.

Just as the USSR overwhelmed Germany on land by producing more munitions and tanks, the US would overwhelm all other states in shipbuilding and aircraft production. The American shipbuilding programme begun in 1940 was unprecedented in scale. The naval yards in New York and Philadelphia could turn out ships at a speed no other power could approach. Some naval yards had a dozen destroyers on the docks at any one time. A single production yard in New Orleans built nearly nine thousand landing craft of the kind used in Normandy. In 1941 the Japanese, British and American navies had been similar in size – about two million tonnes of warships for Japan and 2.5 million each for the US and UK. By 1944 the US had ten million tonnes of warships. Britain’s navy had barely grown and Japan’s had been depleted. In 1944 alone the US launched nine aircraft carriers while producing more aircraft per year than Germany, Japan and Britain combined.

Kennedy doesn’t believe that American war production was in itself decisive, but the effect was clear enough. The major carrier battles in the Pacific, Coral Sea and Midway were the proof. US aircraft launched from fleet carriers in the Philippine Sea eliminated the prospect of Japan as a world power. The US approached Okinawa with two hundred destroyers, 18 battleships, and more than forty carriers to face down no surface opposition. By 1945 only the US and British navies were major forces, and the US dwarfed all other states in terms of naval and air power. It soon acquired nuclear-powered aircraft carriers and submarines. As Kennedy says, ‘shifts in the productive balances’ didn’t just change the face of the war, ‘but were going to be large enough to alter the strategic landscape of the 20th century itself’.

Until the 2010s, there was little talk of challengers to American sea power. It is only recently that China has credibly been described as an aspirant rival at sea. During its continued period of dominance, the US has advanced an image of itself as the protector of freedom at sea, just as Britain once did. Under the Proliferation Security Initiative launched by George Bush in 2003, the US Navy has interdicted, boarded and searched ships as a matter of course. In December 2020, the US military published an official strategy document titled ‘Advantage at Sea’ which claimed that American sea power had assured ‘free and open access to the world’s oceans’, bringing about ‘an extraordinary era of wealth and peace for many nations’. But, it went on, ‘that system is now at risk.’ As a result, the US must ‘maintain and exploit sea control in contested environments from the littorals to open ocean, including critical chokepoints’. The contemporary equivalents of Fisher’s five keys – Malacca, Yokosuka, Hormuz, Suez and Panama – are all either in American hands or as good as. In East and South-East Asia the US has major military facilities on Guam, naval bases in Japan at Yokosuka, Sasebo, Okinawa, Misawa and Atsugi, bases in Thailand and Sembawang, and access to military support facilities in South Korea and the Philippines. To these can be added the US position in the Indian Ocean, based on Diego Garcia, and the Fifth Fleet’s permanent presence in the Persian Gulf.

But in a report to Congress in November 2021 the US Department of Defence declared that China now had ‘numerically the largest navy in the world’. That line, widely reported in international media, is misleading, since much of China’s fleet comprises patrol and logistics vessels. It’s difficult to make a direct comparison between the US and Chinese navies because their ships play different roles. The US has many more destroyers, amphibious assault ships and guided-missile cruisers, as well as by far the best submarine force in the world, with eight times as many nuclear attack submarines than any other state. The majority of China’s submarine force runs on diesel. China didn’t have a domestically built aircraft carrier in service until 2019 and both its carriers (one of them a refitted Soviet ship built in 1985) are half the size of any one of the eleven US vessels. A third Chinese carrier is now being built, but again without nuclear propulsion. China has developed anti-ship ballistic missiles to counter the US carrier fleet, but it’s too soon to know whether they will be decisive. If they are, China will have spent a lot of time and money in foolish emulation of US carriers. In any case the Chinese navy has conducted no military operations of any scale and almost nothing outside its immediate sea perimeter. The US Department of Defence assessment was that the Chinese navy’s ‘ability to perform missions beyond the First Island Chain is modest but growing’. In other words it remains a regional navy.

What is now at stake between the US and China is not global pre-eminence but the shackles the US has constructed around China: the ‘defence perimeter’ around the East and South China Seas, at some points just a few kilometres from the Chinese coast. That explains the focus on Taiwan, to which America sends more than just octogenarian politicians. In February 2021 the US conducted naval exercises in the Taiwan Strait with two aircraft carrier groups. In early August, the US Navy assembled 38 ships and 170 aircraft from allied countries for naval exercises in the Pacific. It’s probably a sign of confidence that American planners have been happy to supply Taiwan with F-16 fighters but haven’t paid much attention to its shore defences. There are signs this may be changing. In August last year, the US signed a deal to supply Taiwan with American howitzers. It has also considered placing large numbers of missiles on the territory of its East Asian allies, and permanently deploying attack helicopter squadrons and artillery in South Korea.

Since 2015 the US has regularly conducted ‘freedom of navigation operations’ in the seas surrounding China. And China has continued to face legal battles over its territorial claims to islands in the South China Sea. When brought to international tribunal by the Philippines, China rejected the tribunal’s jurisdiction, as large powers tend to do. In July 2020, Mike Pompeo accused China of attempting to build a ‘maritime empire’, a statement which ought to have elicited general laughter. As I write, a US carrier group is passing through the South China Sea. The US claims it is conducting a principled defence of free seas; China says that such moves are merely provocations. On 13 July, China claimed that a US destroyer, the USS Benfold, had entered waters off the Paracel Islands, which China claims. The US insisted that the Benfold was in international waters. China sent a frigate to follow it all the way across the Taiwan Strait. These incidents happen so often that they now rarely qualify as news. At its core the dispute is an iteration of an old argument as to whether the claims of maritime empires to freedom of the high seas are anything more than a predatory pretext.