The Dow Jones Industrial Average briefly topped 54,200 on Tuesday, breaking a three-session coil beneath its record, but the breakout didn't stick—surrendering the entire move by the close. The pullback underscored how quickly US-Iran tensions over the Strait of Hormuz can yank the rug from a momentum trade, with investors still jittery over Tehran's stance that Hormuz will stay closed until Washington meets its conditions.

JPMorgan Lifts...