Trump said the 6-month-old Iran conflict is "small potatoes" and backed JD Vance's refusal to call it a war, even after 18 U.S. service members were killed.
He argued the fighting is now intermittent, involves airstrikes rather than U.S. ground troops, and has imposed a relatively lower death toll than past American wars.
Vance had said a day earlier that there was "no active shooting" and declined to predict the conflict would end before the Nov. 3 midterm elections, despite Iran firing at Kuwait on Thursday.
Trump also defended the campaign's cost by saying it has crippled Iran's nuclear program, though the conflict has already run far longer than his initial forecast of only weeks.