The war with Iran is quickly becoming an economic problem for the United States — and a policy dilemma for the Federal Reserve. Rising oil prices, shipping disruptions in the Middle East and fresh signs of weakness in the U.S. labor market are creating a complicated backdrop just as inflation had begun to show some signs of improvement. For policymakers, the risk is a familiar but unwelcome scenario: higher prices paired with slowing growth — a dynamic known as “stagflation” — that could make it harder for the Fed to cut interest rates and ease pressure on American consumers. The national average for gas prices hit $3.41 a gallon on Saturday, according to AAA, rising $0.43 in just the past week. Meanwhile, U.S. crude oil logged its biggest weekly gain on record in data going back to 1983, a sign that gas prices could continue rising in the coming days and weeks. This comes as the Federal Reserve is already grappling with signs of a weakening labor market.…