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Fears of long Iran conflict shake markets

Aug 18, 2026, 9:49am EDT
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A man pumps gas at an Exxon station as the price of oil and gas has surged
Ken Cedeno/Reuters

Government bond yields rose to multiyear highs and stock markets fell on growing concern that tensions between the US and Iran are unlikely to resolve in the near future. Benchmark oil prices also topped $90 a barrel as investors fretted that efforts to reopen the Strait of Hormuz were making little headway.

Worries over inflation because of rising oil prices and threats to key supply-chain chokepoints, as well as huge debt issuance tied to the AI infrastructure boom, drove yields on 30-year US Treasury bonds to nearly their highest level since 2002. Elsewhere, French and German long-dated yields are at their highest since 2008 and 2011 respectively, while Japanese ones are closing in on an all-time record.

US treasury bond yields
— Prashant Rao
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