Since the Industrial Revolution, the currency of international power has shifted from land to commerce. The incoming global maritime order focuses on compounding wealth by minimizing transaction costs, while the outgoing order of competing continental empires focused on pounding each other.1 The old system destroyed wealth; the new one creates it, as the statistics show. In 2020, an article from the Center for International Maritime Security suggested a 66-70-80-90-99 rule, highlighting that 66 percent of global wealth comes from or near the sea; 70 percent of the globe is oceanic; 80 percent of its population is coastal; 90 percent of goods arrive by sea; and 99 percent of international digital traffic goes by submarine cable.2
As the 19th century gave way to the 20th, the United States began its transition from a continental to a maritime security paradigm and, after World War II, became champion of a maritime world order as the result of a three-phase transformation. The U.S. Navy has played a key role in the transition.
A Continental United States
The U.S. conquest of much of North America defined the continental phase. The United States unsuccessfully invaded Canada twice (1775, 1812); negotiated treaties with the British and Spanish empires (straightening the northern border in 1818 and gaining Florida in 1819); cut large checks for the central and western United States (the 1803 Louisiana Purchase from Napoleon Bonaparte and the 1867 purchase of Alaska and points south from Tsar Alexander II); and fought Mexico for Texas and the Southwest (the Mexican-American War, 1846–48).
The Monroe Doctrine, this period’s most famous foreign policy proclamation, was a classic continental, sphere-of-influence, “stay out of my exclusive zone” warning to European powers. Meanwhile, the U.S. Army completed America’s longest war: the conquest of the west, which its original inhabitants fought to retain their lands. It ended in an 1890 massacre at Wounded Knee, the same year Alfred Thayer Mahan published his seminal book, The Influence of Sea Power upon History: 1660–1783, grounded in an understanding that commerce had become the currency of power. Mahan ushered in the second phase of the U.S. maritime metamorphosis when he made the case for investment in a blue-water navy that became the mantra of navalists worldwide.
Becoming a Maritime Power
Much earlier, Britain by necessity had developed a maritime security paradigm suited to its island geography and neighboring large continental foes. Britain’s preeminent maritime theorist, Sir Julian S. Corbett, quotes Britain’s great philosopher, scientist, lawyer, and statesman, Sir Francis Bacon: “[H]e that commands the sea is at great liberty, and may take as much and as little of the war as he will. Whereas those that be strongest by land are many times in great straits.”3
Vice Admiral Satō Tetsutarō, president of Imperial Japan’s Naval War College, published the 1908 History of Imperial Defense, making him among Japan’s most influential naval officers. Satō highlighted the first fundamental discriminator between maritime and continental powers: “Among the Powers in the World, there are only three countries that can defend themselves primarily with navies. They are the UK and the US and Japan.”4 In other words, maritime powers can defend themselves primarily by sea, whereas continental powers cannot. Each must prioritize spending on naval versus ground forces accordingly.
Nicholas Spykman, a naturalized U.S. citizen from Amsterdam, The Netherlands, finished his most famous work, The Geography of the Peace, in 1943 while Nazis occupied his homeland. He emphasized oceans as access both for oneself and for one’s enemies, and ships as the main conduit: “The United States will have to depend on her sea power communications across the Atlantic and Pacific to give her access to the Old World. The effectiveness of this access will determine the nature of her foreign policy.”5 In other words, U.S. security was a function of sea power.
Land powers, however, seek security by accumulating spheres of influence and exclusion zones, often in concentric rings around their borders. Typically, they try to prevent the rise—or seek the dismemberment—of bordering powers. They tend to prefer weak neighbors and have often assumed responsibility for their neighbors’ foreign policies. The Chinese, Mongol, Russian, Napoleonic, Soviet, and Nazi empires followed this pattern.
In contrast, sea powers (such as Britain and the Dutch Republic) have tried to expand the reach of international law and, eventually, of international institutions to share the oceanic commons to trade in safety. Indeed, the Dutch Republic’s Hugo Grotius became the founding father of international law. According to his 1609 Freedom of the Seas: “Every nation is free to travel to every other nation and to trade with it.”6 In Law of War and Peace (1625), he cited the Roman jurist Celsus: “To all men belong the use of the sea,” as well as a Byzantine recodification of Roman law: “By natural law, the following are common to everyone: the air, flowing water, the sea, and in consequence the seashore.”7 Thus, the view of oceans as commons goes far back in Western thinking.
Commerce Over Conquest
Unlike land powers—which face immediate threats on their borders that force a focus on national security—sea powers, given the comparative security afforded by a moat, can focus on national prosperity and oceanic trade as a means to that security. This gives rise to differing preoccupations: Whereas land powers often view both land and sea as sovereign territory and pursue a negative-sum, wealth-destroying quest for its control, sea powers generally view the world in terms of potential markets and maritime commons for positive-sum trade and cumulative economic growth.
Where land powers see territory to be taken, maritime powers see markets to make money. And while land powers divide the world into competing exclusive zones, sea powers desire commons—a shared space—encompassing not only the seas, but in modern times also air, space, and cyber. The land-power imperative for insulation from the world versus the sea-power appetite for global access is a second distinguishing characteristic. From these two discriminators—the in/ability to defend by sea and the desire for open/closed seas—arise two mutually exclusive visions of global order and a source of much conflict.
The transportation revolution arising from the Industrial Revolution upended global economics, with wealth accruing from commerce far outpacing that derived from land. In 1869, the Suez Canal’s completion overturned the economics of the once-lucrative Silk Road, marginalizing formerly coveted real estate from Syria to Afghanistan. Henceforth, sea transport became ever cheaper than land transport, rendering internal lines of communication far less profitable than external ones. The advent of megaships and containerization greatly accelerated the trend.
This is the third characteristic distinguishing sea and land powers—the reliance on internal versus external lines of communication, particularly in wartime. Most significant, external lines connecting the far reaches of the globe can facilitate far-flung alliances.
Rising 20th-century nationalism undermined the economics of both continental and maritime empires by making colonies ungovernable by outsiders unwilling to commit genocide to stay or money sinks for those who remained. World War II and decolonization formed the backdrop to the third phase of the U.S. transformation. The administration of President Harry S. Truman played a key role in the global transition from empires to a maritime, rules-based world order.
Abroad, President Truman supported the creation of the International Monetary Fund (1944), the International Bank for Reconstruction and Development (1944), the United Nations (1945), the General Agreement on Tariffs and Trade (1947; predecessor of the World Trade Organization), the Organization of American States (1948), the North Atlantic Treaty Organization (1949), the European Coal and Steel Community (1951), and the European Economic Community (1957; predecessor of the European Union). At home, Truman created the Council of Economic Advisers in 1946 and—in 1947—the Central Intelligence Agency, the Department of Defense, the Joint Chiefs of Staff, the Air Force, and the National Security Council. The Eisenhower administration doubled down on this foreign and domestic institutional legacy to hold the peace, a task that post–World War I leaders had so conspicuously failed to accomplish.
This legacy makes Truman and Eisenhower’s the greatest U.S. generation, not their children who claimed the title. These Presidents, both veterans of the war to end war, came home to raise families during the Great Depression, only to send their children’s generation to serve in a second world war. Institution-building was the Presidents’ generational response to crisis management when its members rose to leadership roles. They fully understood the costs of not having an institutional international order—two devastating world wars sandwiching a global economic depression—so they built strong institutions to create forums to hash out problems verbally rather than fight them out militarily. Those institutions have held the peace in the industrialized world ever since, though many unindustrialized countries became battlefields instead.
Yet, most countries do not fit cleanly into land or maritime categories. But those lacking a maritime geographic position can gain its benefits by virtue of their friends and the international institutions they support. Alliances can bestow on the whole a collective maritime position and power denied to the parts, by mobilizing not only soldiers and sailors, but also diplomats, lawyers, financiers, and industrialists to wage war in many domains. Land powers focused on negative-sum land grabs from their neighbors make poor partners. Some nevertheless team up at times, but territorial disputes and fears of encroachment by landward neighbors lurk in the background—China and Russia’s predicament. Sea powers do not have this problem since trade, not territory, is their main goal.
A maritime global order gives navies an enormous peacetime role.
The Roles of Navies
Although rarely decisive in wartime, navies have an outsized peacetime role as guardians not only of maritime borders, but also of peacetime commerce, making the navy the service most intimately connected with the civilian economy. Like other services, navies deter attacks on the homeland—most potently through difficult-to-track, nuclear-armed, nuclear-powered submarines—but unlike the others, navies also deter attacks on the commons. Navies minimize piracy, keeping insurance premiums down so that vulnerable merchantmen can deliver goods unmolested and at predictable costs. Without secure maritime commons, international trade would grind to a halt, bottlenecks would choke economies, living standards would crumble, and the win-win, wealth-compounding, global maritime order would unravel.
Contrary to Mahan’s hype about decisive naval battle, armies have more often been decisive, in the sense of the single silver-bullet, war-winning, objective-delivering instrument. Because unassisted ground forces can deliver strategic victory, if the war’s purpose is annihilation of the opposing army, continental powers often equate operational with strategic success. When land was the currency of power, this type of resolution was more possible. Today, no single instrument of power (except perhaps a vaporizing nuclear strike) is likely to be decisive in the instant-communication, rally-the-third-parties present. Even in the past, protracted wars required production, resources, supportive populations, allies, and a long list of complementary capabilities.
Naval forces can target their opposite numbers in wartime, as occurred in the symmetric Pacific fleet-on-fleet battles during World War II. They also can support land forces in peripheral theaters in coastal locations, as in North Africa in World War II. But against a competent land power, navies are unlikely to reach the main theater, probably located inland and defended against coastal attack. They can blockade opposing fleets in port (which eliminates enemy oceanic trade, too), and sea powers’ navies play a huge logistical role in commerce protection through convoys. Land powers may counter with commerce raiding by submarines, but, hemmed in by limited access to the seas, they cannot blockade sea powers’ coastlines.
The rare occasions when navies have been decisive required fabulously incompetent adversaries. Sparta’s destruction of the Athenian fleet at Aegospotami (405 BCE) ended the Athenian empire—but it took a feckless commander to leave his fleet unattended and pulled up ashore to lose it. Tsar Nicholas II ceded Japan its war objective (control over Korea and southern Manchuria) following his fleet’s destruction at Tsushima (1905)—even though his supply lines were exclusively overland, Russians greatly outnumbered Japanese in theater, and one more battle would have defeated an exhausted Japan. Even the brilliant British victory at Trafalgar (1805) that guaranteed against invasion was not decisive: The Napoleonic Wars continued for another decade.
Instead, navies routinely combine with other instruments of national power, particularly diplomacy, to coordinate allies with complementary capabilities; international law to regularize relations; and the economic capabilities of finance, production, and distribution. To defeat Napoleonic France, Britain developed a grand strategy—grand in its integration of multiple instruments of national power. It began with a three-part cumulative strategy.8
First, protect trade and the home economy to prevent invasion and to fund its and its allies’ militaries. Second, simultaneously shut down French trade and access to overseas theaters through blockade to squeeze its economy and throw it back on the resources of its increasingly war-impoverished neighbors. Third, open peripheral theaters with better sea than land access to attrite enemy forces disproportionately, relieve pressure on land-power allies fighting on the main front, and divide enemy attention to predispose overextension.
The Continuum of Peace and War
Cumulative effects fed into an overlapping, sequential strategy to deliver British victory: Immediately find, fund, and arm the most directly threatened land-power ally to pin the French-led army in the main theater. Join the fight on the main front only with multiple allies and after large enemy losses in both the main and peripheral theaters. Thus, dodge the continental enemy’s primary strength—its army—and leverage British strengths: naval dominance, the ability to create wealth, and, therefore, the ability to endure a protracted war. The key: Enable the allies to win. As much as a continental power might wish to follow this strategy, without command of the sea, which surrounding narrow seas and adjacent adversaries make highly unlikely, it cannot. But this strategy requires both maritime access and sanctuary at home, a tall order in today’s era of precision nuclear strike.
After World War II, few were interested in a nuclearized third major war. Containment became the maritime answer to continental problems—leverage external lines of communication to connect a maritime global alliance and wealth-production system. Put time on one’s side by keeping continental problems homebound and let growth compound in the uncontained maritime world, producing an ever starker divergence in productivity and living standards. Eventually, the problems resolved through a change of heart at the top (Mikhail Gorbachev), revolutions from below (Eastern Europe), or ever-deepening decline (Kim Jong-un). During the long wait, land powers suffered from their follies, while citizens of the maritime system prospered.
Navies play an essential role in containment, along a maritime peace-to-war continuum that ranges from antipiracy operations against small players, to sanctions against any-sized players, to blockades against big ones. The continuum focuses on economic denial strategies to dampen enemy growth. An economy doubles in 23 years at a 3 percent growth rate; in 35 years at 2 percent; and in 70 years at 1 percent—revealing the serious compounding effects of shaving down an enemy’s growth rate. Just compare the North and South Korean economies to get a feel for the multigenerational consequences.
This maritime peace-to-war continuum includes a range of sanctions, beginning with I sanction, my friends sanction, and everyone sanctions a targeted country by refusing to buy, sell, or both for one, multiple, or all items. The continuum proceeds to impounding a targeted country’s merchantmen in my ports, my friends’ ports, or all ports. It can escalate further to shutting down SWIFT codes (key identifying information for international banks) to exclude the targeted country from the international banking system. Still more escalatory is commerce raiding, ranging from I hunt, my friends hunt, to everyone hunts the targeted country’s ships. The continuum ends with blockade: leave port and all your ships—merchant or military—will be sunk. The continuum embodies escalatory denial: a time out from the global trading regime for the targeted country. Navies are essential to enforce sanctions—a key peacetime role. They deny desired goods and raise the costs of defying sanctions and finding substitutes, which together suppress growth.
Today, China contests the global order with genocide at home and territorial expansion abroad. China (let alone Russia) cannot exercise a maritime security paradigm without numerous allies. Neither China nor Russia has a moat; rather, no other countries have nearly as many neighbors, let alone so many hostile or dysfunctional ones. China—indeed, any country—can minimize transaction costs only through peaceful cooperation within the maritime, rules-based order. The alternatives are expensive and wealth reducing.
Counterintuitively, China’s defiance of global norms offers a rare opportunity to strengthen Asia’s regional security architecture through the growing participation of its neighbors. The more dire the threat, the stronger the impetus to build, spread, and strengthen countervailing institutions. As much as the United States and others may wish China would become a constructive member of the international system, that choice rests with China, which for the foreseeable future will more likely double down than change heart, as the Chinese Communist Party clings to power. For outsiders, China is a problem more amenable to management than resolution.
The U.S. Navy can play an essential role in coordinating maritime cooperation among China’s many threatened neighbors, so that the accumulating precedents strengthen, rather than weaken, the security architecture of Asia and thereby deepen the global maritime order. Navies are the first responders for institution building—naval exercises can expand, including ever more participants, and institutionalize into permanent coordination and, ultimately, alliance systems. Navies are part of the long game: coordinated prosperity with partners and defense against the defiant to protect us all from a continental relapse.
1. By global order, I mean the international legal rules, applying to both state and nonstate actors, and the institutions that develop, amend, and administer these rules.
2. Lars Wedin, “Sweden and the Blue Society: New Challenges for a Small Navy,” Center for International Maritime Security (CIMSEC), 17 September 2020.
3. Francis Bacon, “Of the True Greatness of Kingdoms and Estates” in Essays Civil and Moral, cited in Julian S. Corbett, Some Principles of Maritime Strategy (New York: Longmans, Green and Co., 1911), 55.
4. Cited in Tadokoro Masayuki, “Why Did Japan Fail to Become the ‘Britain’ of Asia?” in John W. Steinberg, Bruce W. Menning, David Schimmelpenninck Van Der Oye, David Wolff, and Shinji Yokote, eds., The Russo-Japanese War in Global Perspective: World War Zero, vol. 2 (Leiden, Netherlands: Brill, 2007), 301–2.
5. Nicholas J. Spykman, The Geography of the Peace, Helen R. Nicholl, ed. (New York: Harcourt, Brace, and Co., 1944), 57.
6. Hugo Grotius, Freedom of the Seas, Ralph van Demen Magoffin trans., James Brown Scott, ed. (New York: Oxford University Press, 1916), 7.
7. Hugo Grotius, The Law of War and Peace (De Jure Belli Ac Pacis), Louise Ropes Loomis, trans. (Roslyn, NY: Classics Club, 1949), 91–92.
8. The cumulative/sequential strategy distinction comes from RADM J. C. Wylie, USN, Military Strategy: A General Theory of Power Control (1967, reprint; Annapolis, MD: Naval Institute Press, 1989), 117–21.