The Exxon oil refinery in Baytown, Texas, US, on Thursday, March 5, 2026. Mark Felix | Bloomberg | Getty Images Surging oil prices due to the Iran war did not result in a windfall for Exxon Mobil and Chevron in the first quarter. The two biggest U.S. oil companies reported profits on Friday that fell dramatically compared to the same period last year. Exxon's net income declined 45% while Chevron's tumbled 36%. Exxon shares were up more than 1% in premarket trading while Chevron's gained about 2%, as they both beat Wall Street's earnings estimates. Oil prices had been depressed during the first two months of the year as the market anticipated a surplus, but suddenly spiked after the U.S. and Israel attacked Iran on Feb. 28. Prices have surged 57% as the war has caused the largest oil supply disruption in history. "The global energy system continues to be under extreme stress," Chevron CEO Mike Wirth told CNBC in an interview.…