Trade, Not Troops: What the Data Actually Says About Preventing War

As an engineer by training, I am wired to think in terms of systems, signals, and data. When a bridge fails or a circuit shorts, we do not rely on intuition or political rhetoric to diagnose the problem; we examine the stress points, analyze the inputs, and let the evidence lead.

When my colleague Monica Lagazio first proposed using machine learning to analyze interstate conflict, my immediate reaction was to focus purely on the data and ignore ideological biases. The results we uncovered were unexpected and even challenged long-held geopolitical beliefs.

Using Bayesian neural networks and Automatic Relevance Determination to analyze more than a century of data from the Correlates of War project, we set out to identify which factors genuinely correlate with peace. The model weighed military expenditure, alliance networks, regime types, geographic proximity, and commercial ties across generations of geopolitical change.

The result was unequivocal: the strongest predictor of interstate peace was not a nation’s military capability, nuclear posture, or strategic alliances. Rather, it was economic interdependence.

The mathematics of interdependence

To understand this, think about how economic integration alters the motivations for state actions. Conventional security strategies are based on deterrence, trying to make aggression unprofitable by threatening retaliation to outweigh any benefits.

Economic interdependence achieves a similar effect far more efficiently. It makes war costly not by threatening destruction from outside, but by eroding the aggressor’s prosperity from within. When a nation’s supply chains, energy grids, consumer markets, and financial systems are entangled with those of its neighbors, firing a missile becomes an act of self-sabotage. Prosperity ceases to be a zero-sum contest won through territorial expansion and becomes a networked asset that depends on predictable, uninterrupted cooperation.

Most importantly, our models indicate that peace-building factors do not operate independently. Trade, democratic governance, and credible international security arrangements influence each other in a multiplicative rather than additive manner. A country with strong economic ties, democratic institutions, and active engagement in international security is far less likely to engage in militarized conflict compared to one depending solely on military deterrence. Economic connections serve as a force multiplier for stability, transforming formal treaties from mere paper agreements into tangible economic practices.

The misallocation of global capital

Yet look at how the international community actually spends its resources, and our priorities appear inverted. The world spends nearly $2.887 trillion annually on military defense and weaponry, while global trade in goods and services totals $35 trillion each year. One figure represents what humanity spends preparing for destruction; the other, what we earn through mutual exchange.

Security forces and advanced weaponry may deter aggression in a crisis, but they are inherently reactive and address symptoms rather than root causes. Commerce, by contrast, builds the structural conditions that make conflict unthinkable in the first place. Deterrence buys time; integration builds peace.

This places economic institutions like the World Trade Organization (WTO) squarely on the front lines of global security. The WTO is often dismissed as a slow-moving, bureaucratic forum for commercial disputes. In truth, it is one of the world’s most consequential peace-building mechanisms. By enforcing predictable rules, lowering tariffs, and resolving friction before it hardens into nationalist feuds, the WTO reinforces the very interdependence that keeps the peace.

As protectionism rises, supply chains fragment, and leaders champion “de-risking” by shifting toward isolated blocs, we risk dismantling the economic architecture that has prevented catastrophic systemic war for nearly eight decades. Defending the multilateral trading system is not merely an economic preference; it is a national security imperative.

A data-driven framework for statecraft

Translating these findings into policy requires a significant shift in how leaders approach conflict prevention. The policy implications are straightforward.

First, governments should focus on regional trade integration, especially among neighboring countries with a history of rivalry, because stronger trade ties foster shared economic interests that turn potential conflicts into opportunities for cooperation and mutual benefit.

Second, vulnerable economies must be safeguarded from the misuse of economic interdependence, ensuring that trade serves as a means for shared prosperity rather than as leverage for coercion or geopolitical dominance.

Third, democratic institutions need reinforcement, since the benefits of economic integration are maximized when accompanied by transparent, accountable, and rule-based governance.

Lastly, countries should maintain credible defense capabilities while gradually shifting their security strategies to invest more in economic and institutional foundations of peace; letting trade, diplomacy, and shared interests foster stability and reduce dependence on military deterrence over time.

While trade is not a cure-all and no economic approach singly guarantees security in an uncertain world, the evidence shows that lasting security is built through markets, rule of law, and shared economic interests.

If we want a stable global order, we must stop treating trade as a dividend of peace, and start investing in it as peace’s primary engine.