very policy is a prediction. Tax cuts will boost the economy. Sanctions will slow Iran’s nuclear program. Travel bans will limit the spread of COVID-19. These claims all posit a causal relationship between means and ends. Regardless of party, ideology, or motive, no policymaker wants his or her recommended course of action to produce unanticipated consequences. This makes every policymaker a forecaster. But forecasting is difficult, particularly when it comes to geopolitics—a domain in which the rules of the game are poorly understood, information is invariably incomplete, and expertise often confers surprisingly little advantage in predicting future events.

These challenges present practical problems for decision-makers in the U.S. government. On the one hand, the limits of imagination create blind spots that policymakers tend to fill in with past experience. They often assume that tomorrow’s dangers will look like yesterday’s, retaining the same mental map even as the territory around them changes dramatically. On the other hand, if policymakers addressed all imaginable threats, the United States would need so large and expensive a national security establishment that the country could do little else. By many measures, it is nearing this point already. The United States has military bases in more than 70 countries and territories, boasts more than four million federal employees with security clearances, and fields 1.3 million active-duty troops, with another million in reserve. According to one estimate, the United States spends $1.25 trillion annually on national security. When it comes to anticipating the future, then, the United States is getting the worst of both worlds. It spends untold sums of money preparing yet still finds itself the victim of surprise—fundamentally ill equipped for defining events, such as the emergence of COVID-19.

There is a better way, one that would allow the United States to make decisions based not on simplistic extrapolations of the past but on smart estimates of the future. It involves reconciling two approaches often seen to be at philosophical loggerheads: scenario planning and probabilistic forecasting. Each approach has a fundamentally different assumption about the future. Scenario planners maintain that there are so many possible futures that one can imagine them only in terms of plausibility, not probability. By contrast, forecasters believe it is possible to calculate the odds of possible outcomes, thereby transforming amorphous uncertainty into quantifiable risk. Because each method has its strengths, the optimal approach is to combine them. This holistic method would provide policymakers with both a range of conceivable futures and regular updates as to which one is likely to emerge. For once, they could make shrewd bets about tomorrow, today.

…MORE