New Delhi, Aug. 1 -- HOUSTON - The Iran war has cost governments, shippers, and consumers across three continents. For ExxonMobil and Chevron, it has been the most profitable operating environment in years.

Both companies reported second-quarter earnings on Thursday that surpassed analyst estimates by wide margins, driven by crude oil realizations above $90 a barrel across their upstream portfolios. Chevron posted what Fortune described as its largest quarterly profit ever. Exxon's net income surged on the back of upstream volumes that ran at near-maximum capacity as Brent crude averaged above $100 a barrel through most of June and July. The two reports, arriving on the same Thursday, put a price tag on the supply disruption that the Ira...