The first revision to gross domestic product for the first quarter of 2026 comes out Thursday, and it could clarify whether the Iran war has hurt the fairly positive momentum of the U.S. economy.The Bureau of Economic Analysis revises its GDP calculation a few times. Its initial estimate came in showing that the economy grew at an annual rate of 2% at the start of the year. The upcoming revision will fill in more data, particularly for the month of March, which was the first full month of the war in Iran.The revised data could have both positive and negative effects on each of the components that make up GDP.Take net exports: The U.S. now sends a lot of oil and gas overseas, so the spike in prices might drive that number up and raise overall GDP, said Eswar Prasad, professor of trade policy at Cornell University.“Even if the volumes of U.S. exports, especially energy exports, stayed the same, just the increase in prices could have given a bit of a boost to exports,” he said.On the flip side, the first quarter was also when President Trump’s tariffs were struck down by the Supreme Court, which may have led to more imports. That would pull GDP down.The next component of GDP is business investment. In the last few quarters that’s basically meant investment in artificial intelligence data centers. The revision will give us a sense of whether companies have been stocking up to build those data centers, said JoAnne Feeney, a portfolio manager and partner at Advisors Capital Management.“If inventory growth was faster than expected because of the preparation to build those data centers, then that would contribute to faster GDP growth than we thought a month or so ago,” she said.Then, there’s government spending, which helped drive up GDP in the first quarter, as the government shutdown ended and the war with Iran began.The last piece of the puzzle is consumer spending. So far, it doesn’t look terrible, said Steven Blitz, chief U.S. economist at GlobalData TS Lombard. But it did slow down a bit.“Just enough to be sort of a dampener on growth,” he said.All this adds up to a sort of unsteady expansion, Blitz said. An economy that’s wobbling — not into a recession, but onto a slower path.