Trade Wars Are Class Wars: How Rising Inequality Distorts the Global Economy and Threatens International Peace: Summary & Key Insights

After World War II, the architects of the global economy recognized that balance mattered—not only between nations, but within them. The Bretton Woods system, led by figures like Keynes and White, was built to ensure that no country could grow at the expense of another without consequence. Domestic demand was maintained by rising wages and widespread consumption. When workers shared in productivity gains, the world economy stayed balanced: American laborers could afford the goods they produced, European societies rebuilt with strong welfare states, and global trade expanded sustainably.

Yet by the late twentieth century, this equilibrium began to fracture. The liberalization of capital flows, deregulation, and the political shift toward market fundamentalism altered the equation. The postwar compact between labor and capital weakened. Governments became less willing—or less able—to manage income distribution, and workers’ bargaining power eroded under the pressures of globalization and automation. Meanwhile, household consumption—especially in the advanced economies—stagnated, while savings grew among the wealthy and within corporate sectors.

The authors trace how this structural change reconfigured the entire global economy. The United States, once the world’s great exporter, turned into the consumer of last resort, absorbing the excess production of others through growing deficits. China, emerging from reform and industrialization, pursued export-led growth as a development strategy but relied on suppressing domestic consumption to sustain it. Europe, too, became unbalanced: Germany’s surpluses mirrored the debts of its southern neighbors. The cohesive system that once balanced production and demand globally gave way to one polarized between savers and spenders, lenders and borrowers—class divides projected onto the international stage.

To understand how inequality drives trade conflicts, Pettis and Klein build a deceptively simple model grounded in the relationship between income, savings, and consumption. Every economy must balance its output with its spending: what is produced must be bought by someone. When income is distributed evenly, most of it is spent on goods and services, maintaining strong domestic demand. But when income pools among the wealthy or among firms that save rather than consume, aggregate spending falls short of potential output.

This excess of production relative to consumption shows up as a surplus of savings. Economists often frame this as a virtue, but in the authors’ framework, an economy that saves more than it invests domestically must export its surplus savings abroad—often in the form of lending to deficit countries. Those borrowing countries, to maintain growth, run trade deficits, importing more than they export to absorb the world’s excess production. Thus, domestic inequality in one country generates international imbalances.

The mechanics are clear in accounting terms, but the deeper insight lies in the politics of distribution. The authors argue that these dynamics are not the result of ‘competitiveness’ or ‘industrial efficiency’ but of who gets paid and who gets left out. In countries where workers capture less income, households cannot spend enough to sustain output, pushing the national savings rate up artificially. Conversely, in countries where inequality leads to debt-fueled consumption, deficits emerge—not because citizens lack discipline, but because their incomes cannot keep pace with the costs of living. The world’s trade tensions thus reflect a struggle between those with excess capital to lend and those who must borrow to fill the gap.