TOKYO—One of the major surprises about the gravest energy shock since the 1970s is how resilient much of the world has been so far.
The closure of the Strait of Hormuz has yanked around 13 million barrels of oil a day from global energy supplies. Blackouts have hit Pakistan, the Philippines has imposed a four-day workweek, and countries including Slovenia and Bangladesh have rationed fuel. The risk that the world sinks into recession is rising with each day the waterway remains shut. The price of Brent crude, the global oil benchmark, has risen more than 50% since the strait was closed.
Even so, in the two months since the strait was closed by Iran in response to U.S. and Israeli attacks, many of the world’s major economies have been soldiering on in contrast to the swift downturns that accompanied similar energy crises in the 1970s and 1990s. Stock markets are touching record highs.
This resilience reflects ample energy reserves, policies to help consumers, and the offsetting effects of the artificial-intelligence boom that is powering trade and business investment in the U.S. and beyond.
It also highlights an underappreciated shift in the workings of the global economy. Over the years, countries have become steadily more energy efficient, squeezing more economic activity out of each drop of oil or cubic meter of natural gas burned. The energy needed to generate a dollar of gross domestic product, adjusted for inflation, has since 2000 fallen by about a third in the U.S. and Europe and by about 40% in China, according to World Bank data.
Better energy efficiency “cushions the shock” from supply disruptions, International Monetary Fund Managing Director Kristalina Georgieva said in April. Underlining the global economy’s resilience, the IMF said that assuming energy flows through the strait resume by midyear, it expects only modestly slower growth this year than in 2025, at around 3.1% versus 3.4% last year.
Of course, a more severe test of the global economy’s durability will occur if the conflict persists and the strait stays closed. The cease-fire between the U.S. and Iran is holding, but so far there is no agreement to reopen the waterway, which is also subject to a U.S. blockade aimed at starving Iran of imports and revenue.
Poor countries that don’t have reserves to draw on and are on the sidelines of the AI boom are already struggling, with shortages closing factories and high import prices for energy straining threadbare government budgets.
If the strait remains closed into next year, the IMF warned global growth in 2026 could sink to around 2%, bringing the world economy close to recession.
When Russia’s invasion of Ukraine triggered a similar energy shock in 2022, consumer prices were already surging in big economies as pent-up demand collided with strangled supply as they reopened after the pandemic.
Central banks had little choice but to jack up interest rates almost immediately. This time around, central banks don’t face the same pressure from domestic inflation as they weigh the risks from a bump in global energy prices. Central banks in the U.S., Europe and Japan held their benchmark interest rates steady this week as they assess the effects of the war on their economies.
“The economic outlook remains highly uncertain, and the conflict in the Middle East has added to this uncertainty,” Federal Reserve Chair Jerome Powell said Wednesday.
Compared with 2022, “the starting point is more benign,” said Mansoor Mohi-uddin, chief macro strategist at the Bank of Singapore, a private bank. Government spending on defense and other priorities is also helping economic activity while the strait remains closed, he said, though he added he is concerned that higher prices and shortages could start to bite within weeks.
Since the closure of the strait, governments have swung into action to stabilize energy supplies and keep a lid on price rises for consumers.
Key to their efforts are deep reserves. Japan and Korea had around 200 days’ worth of reserves on hand in January, according to the International Energy Agency. Europe had 130 days’ supply. China’s enormous stockpile, estimated by the U.S. at around 1.4 billion barrels, is enough to power its economy for about 100 days.
For Asia especially, another counterweight to strains from the energy shock has been buoyant exports. The AI boom has meant ravenous demand in the U.S. and elsewhere for Asia-made chips, electronics and machinery to power data centers.
Exports from Japan were 12% higher in March than a year earlier. In South Korea, they rose almost 50% and in Taiwan, they rocketed 68%.
“AI is papering over the cracks,” said Stefan Angrick, head of Japan and frontier markets economics at Moody’s Analytics in Tokyo.
A deeper reason for the global economy’s resilience compared with previous energy shocks is greater energy efficiency. Advanced economies have shifted to less energy-intensive services such as finance and healthcare from more energy-hungry manufacturing.
Renewables have also played a role—both solar and wind lose less energy as heat than burning fossil fuels. Consumer appliances have been re-engineered to use less electricity and firms have squeezed out improvements in industrial processes to save energy.
German engineering giant Thyssenkrupp has improved its use of energy through measures including capturing waste heat, reducing leaks and replacing lighting and other components with newer, more energy-efficient alternatives, according to recent disclosures on its sustainability efforts.
France’s Saint-Gobain, a construction firm, said in a 2025 report that it has started using AI to monitor and adjust energy use in its fiberglass furnaces to boost efficiency, and is replacing natural gas with more efficient fuels such as hydrogen. Modeling by the IMF suggested that energy-saving measures adopted by European companies in the aftermath of the 2022 crisis reduced by about one-third the long-term damage to the European economy.
With this latest energy crisis, some economists worry about how many more shocks the global economy can take. Hits from the pandemic, energy and U.S. tariffs are causing ripples that could outlast the shocks themselves, such as weaker investment, subdued business and consumer confidence, and strained public finances, said Aaditya Mattoo, director of development research at the World Bank.
“You have this succession of shocks,” Mattoo said. Countries, especially developing ones, “face this tough trade-off between providing relief today and sustaining growth tomorrow.”
Write to Jason Douglas at jason.douglas@wsj.com