Oil, War, Weak Growth and Higher Inflation: How the Middle-East Conflict Is Rewriting the Global Economic Outlook
Former Global Chief Economist for JPMorgan Chase (Ph.D in Economics) & Current Global Keynote Speaker
The escalating tensions between the United States and Iran have triggered a classic geopolitical shock in a fragile global economy, with effects extending beyond the Gulf region. The economic impact has permeated energy markets, financial conditions, trade flows, and consumer and business confidence. While conflicts are often viewed through military or diplomatic lenses, their economic consequences can be just as significant, especially when they involve the Middle East, a crucial region for global energy supplies. This situation is further highlighted by the growing divide among major international economic institutions—particularly the cautious approach of the OECD versus the more bullish forecasts of the IMF and World Bank—illustrating how the conflict’s economic fallout is unfolding. Below is a nonpartisan review of the impact of the recent U.S.-Iran conflict.
The most immediate and visible way a U.S.-Iran conflict impacts the global economy is through energy prices. Iran’s proximity to the Strait of Hormuz (which I covered in a previous Substack article) is a crucial choke point through which about one-fifth of the world’s energy supply passes. This means that any disruption, whether real or perceived, has generated a risk premium in global energy prices. Even without direct supply disruptions, increased uncertainty alone can lead to speculative rises in energy prices. These increases, in turn, affect the global economy by increasing costs for transportation, manufacturing, and household expenses. For the U.S., even though it is a major energy producer, its economy remains closely tied to global oil markets. As a result, higher global prices will lead to higher domestic gasoline prices, heating costs, and broader inflation pressures.
This inflationary shock is especially important in the current macroeconomic environment, where central banks are working to bring inflation back to target levels after the post-pandemic spike. A persistent rise in energy prices constitutes a cost-push shock, complicating policy decisions for the Federal Reserve and other central banks. Higher energy costs directly increase headline inflation and feed into core inflation through increased transportation and production expenses. As businesses pass these costs on to consumers, this leads to a widespread rise in prices for goods and services. Simultaneously, higher energy prices diminish real household income, cutting into discretionary spending and weakening overall demand. This combination—rising inflation alongside slowing growth—heightens the risk of stagflation, a situation that policymakers have historically found challenging to control.
The idea of demand destruction is crucial to understanding this process. As households spend more of their income on basic energy costs, they have less to spend on non-essential goods and services. This change in spending decreases economic activity in many sectors, from retail and travel to manufacturing durable goods. In the United States, where consumer spending accounts for about two-thirds of GDP, even a slight shift in buying habits can greatly affect overall economic growth. The outcome is a negative feedback loop where rising energy prices drive inflation higher and slow down economic growth—a double challenge that’s especially difficult for an economy already coping with high interest rates and tighter financial conditions. These negative economic headwinds have not gone unnoticed in U.S. equity markets, where the S&P 500 Index, which measures U.S. equity market activity, was down 6.0% year-to-date at the time of this writing.
Source: Yahoo Finance
Globally, the impact is even more significant, especially for energy-importing economies in Europe and parts of Asia. The OECD’s recent decision to keep a relatively cautious growth outlook reflects the realization that the Middle East conflict has effectively “knocked the global economy off a stronger growth path.” This contrasts with earlier forecasts from the IMF and the World Bank, made before the escalation of tensions and therefore not fully accounting for the conflict’s economic effects. As a result, the IMF’s global growth forecast of about 3.3 percent for 2026 and the World Bank’s estimate of around 2.6 percent are also likely to be revised lower once their updated projections are issued later in the year.
The OECD’s recent cautious forecast, released this week, which considers the effects of the U.S.-Iran conflict, predicts that global economic growth will slow to 2.9% in 2026, down from 3.3% in 2025. Unlike the IMF, which often emphasizes resilience and structural growth drivers such as technological innovation, the OECD places greater weight on cyclical headwinds, policy uncertainty, and structural constraints, including aging populations and labor market rigidities. This methodological difference has important implications for how each institution interprets the economic impact of geopolitical shocks. In the current context, the OECD’s emphasis on persistent inflation risks and tighter monetary policy aligns more closely with the likely consequences of sustained higher energy prices.
Historical evidence suggests that all major international organizations exhibit some degree of optimism bias, particularly during periods of economic stress. However, the degree of optimism varies systematically. The IMF is generally the most optimistic, often projecting stronger growth based on assumptions about policy support and structural resilience. The World Bank tends to occupy a middle ground, incorporating a more cautious assessment of risks, particularly for developing economies. The OECD, by contrast, is typically the least optimistic, frequently projecting slower growth and highlighting downside risks. In terms of forecast accuracy, research indicates that the World Bank’s projections are the most reliable, followed by the IMF, with the OECD trailing slightly, particularly in anticipating business-cycle turning points.
For the United States specifically, the economic implications are multifaceted. On one hand, higher energy prices can benefit domestic oil producers, supporting investment and employment in the energy sector. On the other hand, these benefits are typically outweighed by the broader negative effects on consumers and energy-intensive industries. Higher gasoline prices act as a tax on households, reducing disposable income and dampening consumption. At the same time, increased input costs for businesses can lead to margin compression, reduced investment, and, in some cases, layoffs. The net effect is a slowdown in economic growth, even as inflation remains elevated. Ironically, for China, despite some short-term pain from higher energy prices associated with the U.S.-Iran conflict and demand destruction effects on its exports, the country may benefit as it pivots towards greater electrification and the use of green energy, which would make the country less vulnerable to higher oil prices.
Credit Markets
Credit markets also play a critical role in transmitting the effects of geopolitical shocks. Heightened uncertainty tends to increase market volatility, widen credit spreads, and tighten financial conditions, reflecting higher inflation expectations and flight-to-safety demand. For policymakers, these developments complicate the task of calibrating monetary policy, as they must balance the need to contain inflation with the risk of exacerbating an economic slowdown. Still, at this time, the effects of higher inflation appear to be dominating U.S. credit markets as evidenced by the recent uptick in U.S. bond yields.
Source: CNBC
Consumer Are Raising Their Expectations of Inflation
Concerns about rising inflation expectations were reflected in the latest University of Michigan’s one-year-ahead inflation expectations (released on March 27, 2026), which increased to 3.8% from its mid-month reading of 3.4%. Consumers are paying attention to higher gasoline prices and expect inflation to rise further in the coming year.
Source: University of Michigan Survey (March 27, 2026)
Summary and Concluding Thoughts
The economic impact of the conflict extends beyond energy-importing countries. Even oil-exporting nations may encounter difficulties, especially if rising prices cause a drop in global demand and trade volumes. Additionally, geopolitical instability can interrupt investment flows, supply chains, and regional economic integration. For emerging markets—which are often more susceptible to external shocks—the combination of higher energy costs, tighter financial conditions, and weakened global demand can be especially harmful, raising the likelihood of balance-of-payments crises and debt problems.
The broader implication is that the conflict between the U.S. and Iran functions as a negative supply shock to the global economy, like previous energy crises. These shocks typically lead to higher inflation and reduced growth, a pattern already evident in the OECD’s forecasts. As the IMF and World Bank update their predictions to account for these effects, their outlooks are likely to align more closely with the cautious estimates currently issued by the OECD.
This means the economic effects of the U.S.-Iran conflict are likely to be immediate and extensive, impacting inflation, growth, and financial stability in the United States and within the global economy.
As energy prices rise across the economy, driving up costs and diminishing purchasing power, the probable result is a period of elevated inflation paired with sluggish growth—posing challenges for policymakers and financial markets. The evidence so far suggests that the global economy is entering a more vulnerable phase, in which geopolitical events could significantly affect economic performance and inflation risks.