The Iran war is starting to show up in the U.S. economy in ways both obvious and not so much, with soaring energy costs leading the impact and potential hits on broader growth simmering beneath the surface. Though recession fears have grown since the fighting began more than six weeks ago, most economists think the war will have only modest effects on gross domestic product — maybe shaving off a few tenths of a percentage point overall. But there's an important caveat, mainly around duration: