The Economic Causes of War
Preface
We are accustomed to viewing the relationship between war and the economy as a one-way street: wars destroy economies, and economic recovery follows in their wake. The literature on how conflict reduces GDP, spikes inflation, and burdens governments with debt is vast and well-documented. Yet, we rarely ask the reverse question: how does the economy drive nations toward war? Historically, we notice these economic precursors only after the first shots have been fired. This book aims to correct that asymmetry. It argues that war is not merely a political failure, but often an economic inevitability—a predictable outcome of resource scarcity, trade collapses, and fiscal stress. To understand the economic roots of conflict, we must first dismantle the modern illusion that financial markets operate in a vacuum. Recent analysis of the relationship between the S&P 500 and 10-year Treasury yields reveals a complex, bidirectional feedback loop. While headlines often simplify this as a direct cause-and-effect, the reality is more nuanced. The correlation between stocks and yields is not universal; it is conditional on the current yield regime. When yields are low, stocks and bonds often move together, driven by growth optimism. But when yields push above a critical threshold—around 4.5%—the relationship inverts. Rising yields then act as a drag on stock valuations, particularly when driven by inflation rather than growth. This dynamic is not static. The "initiator" of market moves shifts depending on the shock: whether it is earnings data, inflation reports, or geopolitical risk. This mirrors the broader economic landscape, where no single factor drives outcomes; rather, it is the convergence of multiple economic pressures that creates instability. The fundamental problem is that each of these signals is consistent with benign explanations. Rising military spending can be deterrence; a commodity spike can be a supply shock; trade friction can be a negotiating tactic. The signals only become unambiguous in their combination and sequence. By the time the convergence is clear, political decisions have often already been made. This book does not offer a crystal ball. Instead, it provides a framework for reading the convergence of economic indicators. By synthesizing insights from international relations, economics, and history, we can move from reactive analysis to proactive awareness. The causes of war are not hidden; they are written in the balance sheets, trade flows, and resource strategies of nations. It is time we start reading them.
Contents
Chapter 1. Resource Scarcity: The most ancient driver of conflict. Nations lacking critical resources, such as oil or minerals, face structural constraints that can shape aggressive foreign policy. The "rapacity effect" quantifies this: a rise in the value of strategic exports increases the risk of conflict.
Chapter 2. Economic Growth as a Catalyst: Contrary to the belief that prosperity prevents war, sustained economic growth can actually increase the likelihood of interstate conflict. Prosperity generates surpluses that fund military expansion, leading to elite and mass optimism about the use of force.
Chapter 3. Arms Race Escalation: Military spending often follows a self-reinforcing spiral. As one nation increases its defense budget, others follow, creating a security dilemma that makes war more likely.
Chapter 4. Trade Collapse and Protectionism: The path to war is often paved with declining trade. The 1930s saw a dramatic shrinkage in global trade following protectionist policies, fostering economic nationalism and isolationism. Bilateral trade deterioration, rather than aggregate globalization trends, is a more reliable predictor of conflict.
Chapter 5. Commodity Price Shocks: Sustained spikes in oil, food, or strategic materials create the conditions for both interstate and intrastate conflict. These shocks erode purchasing power, widen trade deficits, and can trigger social unrest.
Chapter 6. Inflation and Fiscal Stress: When governments face the choice between austerity and inflation to fund military buildups or economic stimulus, the inflation path tends to destabilize the political order. Historical examples, such as German hyperinflation, show how economic chaos can pave the way for extremism.
Chapter 7. Resource Stockpiling: The most observable short-term signal of impending conflict is the strategic accumulation of resources. Bulk purchases of food, fuel, and essential materials, often accompanied by anomalous import surges, can indicate preparation for war.
Chapter 8. Unequal Growth and Inequality: Unbalanced economic growth leads to declining social cohesion and weakening political stability. High inequality, combined with a large population of young males with few economic opportunities, creates a fertile ground for conflict.
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Chapter 1
Resource Scarcity: The Most Ancient and Persistent Driver
The most reliable predictor of war is not ideology, religion, or the ego of a dictator. It is geography and geology—the accident of what lies beneath your soil and what flows through your rivers. We like to tell ourselves that modern warfare is fought over principles: democracy versus authoritarianism, freedom versus tyranny. These narratives are comforting because they make conflict feel moral and therefore inevitable in a cosmic sense. But strip away the propaganda posters and the speeches, and you almost always find the same ledger entry: someone needed something they did not have, and someone else had it. Resource scarcity is the oldest driver of human conflict. It predates written language, predates currency, predates the state. When the game ran out, tribes fought. When the topsoil blew away, nations cracked. When the wells ran dry, empires marched. What has changed is not the underlying mechanism but its scale. A Bronze Age king fought over a copper mine; a twentieth-century dictator fought over an oil field; a twenty-first-century superpower fights over semiconductor-grade silicon and rare earth oxides. The commodity changes. The logic never does.
The Peloponnesian Pattern
Twenty-four centuries ago, a historian named Thucydides wrote the founding text of international relations theory, and he got the economics right before anyone had invented the term. Everyone quotes his famous line—that the growth of Athenian power and the fear it caused in Sparta made war inevitable—but fewer notice how he described that growth. He framed it in terms of wealth, tribute, and trade routes. Athens was a commercial empire. Its power rested on the Delian League's tribute payments, on control of the grain shipments from the Black Sea, on the silver mines at Laurion that literally minted the navy that enforced its will. Sparta was an agrarian land power with stagnant output and a shrinking citizen class. The war was, at its economic core, a collision between a rising mercantile state hungry for grain and markets and a declining terrestrial power desperate to prevent encirclement. When Athens launched the Sicilian Expedition—its catastrophic overreach—it was not pursuing glory. It was chasing grain supplies and new revenue streams to fund a war it could no longer afford. The fleet was destroyed. The empire followed. Thucydides' insight remains the clearest statement of what economists now call power transition theory: wars become most likely not when powers are equal, but when a rising power's economic trajectory threatens a declining one's position. The trigger is rarely the resource itself. It is the uneven growth rate—the terrifying awareness that if nothing is done now, the balance will shift permanently against you.
Germany and the Petroleum Trap
If antiquity provides the theory, the Second World War provides the definitive case study—and it begins with a barrel count. By 1937, the numbers were grotesque. The United States produced roughly 1,279 million barrels of crude oil that year. All of Europe, from the Soviet fields at Baku to the small pools of Romania and France, managed about 56 million. America alone pumped more than twenty-two times the output of the entire continent it was watching arm itself against. This single statistic explains more about the shape of the war than any speech Hitler gave. Germany entered the conflict with essentially no domestic oil. Its synthetic fuel program—hydrogenation of coal into liquid hydrocarbons—was a genuine engineering marvel and ultimately a strategic dead end. It required enormous capital, immense quantities of hydrogen, and refineries that became the highest-priority bombing targets of the Allied air campaign by 1944. Rubber came from synthetic Buna, inadequate for tires at scale. Chrome, tungsten, manganese, bauxite—all imported, all vulnerable. Every major German strategic decision of the era reads as an attempt to solve this equation. The Molotov-Ribbentrop (1939) non-aggression pact with Stalin was, among other things, a supply contract. The secret protocols and subsequent economic agreements delivered Soviet grain, oil, and raw materials through Poland and the Baltic states while Germany fought in the West. When that pipeline faltered, so did the rationale for restraint. The Operation Barbarossa (1941) invasion of the Soviet Union was framed in the ideological terms of "Lebensraum," and anti-Bolshevism, but the operational objectives were geographically explicit. Army Group South drove toward Ukraine's agricultural base and, critically, toward the Caucasus oil fields at Maikop, Grozny, and Baku. Fall Blau, the 1942 summer offensive, sacrificed the Stalingrad front to reach them. Germany lost both. Rommel's North African Campaign, intended to threaten the Suez for its own sake, pointed toward the Iraqi and Persian oil fields to relieve the fuel starvation that plagued every Panzer division in the desert. Rommel's retreats were almost always forced not by British tanks but by tanker sinkings in the Mediterranean. At El Alamein, his armor sat immobilized for lack of gasoline. The ultimate irony is that Germany's resource desperation created a strategic trap of the classic kind. Every solution required seizing territory that demanded more troops to hold, which consumed more fuel to transport, which required seizing more territory. It was a doom loop disguised as a war of maneuver. By late 1944, the Luftwaffe was grounded for want of aviation fuel, and training flights were canceled. It was an army defeated by arithmetic. Japan ran the same script on the Pacific side of the ledger. Facing an American oil embargo in mid-1941 after the occupation of southern Indochina, Japan had an estimated twelve to eighteen months of stockpiled petroleum. The attack on Pearl Harbor was not a bid for conquest of the United States—a nation its own planners understood it could not defeat. It was a gamble to buy time for the seizure of the Dutch East Indies' oil fields, which it accomplished within months. The entire Pacific War was, structurally, a resource raid conducted under the assumption that American industrial capacity would take too long to mobilize. It took less than two years. For decades after 1945, economists believed that resource wealth pacified nations. Trade made war irrational; mutual dependence made it obsolete. The "capitalist peace" thesis held that commerce was the solvent of conflict. Then the post-Cold War data arrived, and it told a different story. Paul Collier and Anke Hoeffler's landmark work on civil war risk found that primary commodity exports were not a shield but a target. Their model showed that economies dependent on resource extraction faced dramatically elevated risks of internal conflict—not because poverty made people desperate, but because valuable, lootable resources made rebellion financeable. Diamonds, timber, coltan, cobalt, oil: these are assets that can be seized, sold on world markets, and converted into weapons. The World Bank formalized this as the "rapacity effect." The finding is disarmingly simple: a 10% increase in the value of oil or mineral exports raises the probability of armed conflict by approximately 2.2%. It is saying that valuable countries fight—or rather, that countries whose soil contains concentrated, high-value, geographically fixed wealth become prizes. The effect operates in two directions simultaneously. Rebel movements form around resource rents because controlling a mine or wellhead is a viable business model. Sierra Leone's blood diamonds, the Niger Delta's oil militancy, the Democratic Republic of Congo's coltan wars—each is a conflict where the fighting pays for itself. Neighboring states face temptation when a weak country holds valuable deposits. Rwanda's and Uganda's interventions in Congo in the late 1990s were justified in security terms and financed substantially by mineral extraction. The mechanism is what economists call the "resource curse" reframed as a security problem. Resource wealth concentrates income in a narrow elite and a narrow geography, hollows out institutions, and creates a state worth capturing. When the state is weak enough to capture and the prize big enough to justify the effort, someone tries.
The Modern Map
It would be a mistake to treat this as history. The resource drivers of 1937 have been updated, not retired. Consider the current configuration. Oil still anchors the system—the Strait of Hormuz carries roughly a fifth of global petroleum consumption, and every military planning staff in the world maintains contingency plans for its closure. But the frontier of scarcity has shifted toward materials that didn't appear in 1940s ledgers. China controls roughly 60–70% of rare earth processing capacity and dominates several critical mineral supply chains. Rare earths are not actually rare in the ground; they are rare in being economically separable from radioactive ore, and that separation capability took decades and enormous environmental cost to build. That concentration is a strategic chokepoint that no amount of mining in Nevada or Sweden immediately resolves. Lithium, cobalt, nickel, and graphite determine who builds batteries, and therefore who builds electric vehicles, grid storage, and increasingly, defense systems. The Democratic Republic of Congo produces the majority of the world's cobalt and has endured three decades of armed conflict directly tied to mining control. Semiconductor fabrication depends on ultra-pure water, specific gases, and a handful of firms producing extreme ultraviolet lithography equipment. Helium, essential for certain manufacturing and medical processes, comes from a tiny number of geological structures worldwide. Fertilizer—synthesized nitrogen—depends on natural gas, which is why a war in Ukraine reverberated through food prices in North Africa. Each of these is a potential Molotov-Ribbentrop moment waiting to happen: a state facing structural dependence on a supplier it distrusts, calculating whether to secure access through agreement, coercion, or seizure.
Why We Always Miss The Signs
Resource scarcity is visible in real time. Commodity prices are public. Reserve estimates are published. Shipping manifests exist. And yet we consistently fail to read them as precursors to conflict, for the reason introduced earlier: every signal has a benign alternative explanation. A country stockpiling copper might be building infrastructure. A surge in fertilizer imports might reflect good farming weather. A naval exercise near a shipping lane might be routine. The signals only cohere in combination. Germany's synthetic fuel investment, its rubber rationing, its diplomatic overtures to Moscow, its troop dispositions toward the east, and its public rhetoric about autarky formed a pattern only legible in aggregate. Individually, each item had an innocent reading. Together, they spelled out a war plan. That is the burden this book takes up. Resource scarcity is not a footnote to geopolitics; it is the substrate upon which geopolitics is written. Ideologies recruit soldiers. Resources give them a reason to march and a means to keep marching. Understanding which resources matter, who holds them, and which states are running short is not economic trivia. It is early-warning intelligence.
The next chapter turns to a paradox that seems to contradict everything here: that prosperity itself, sustained and confident, may be among the most dangerous conditions a nation can experience.