The Iran war has generated uncertainty over the economic outlook and has driven energy prices higher, intensifying inflationary pressure and creating a quandary for Fed policymakers. (AP Photo/Jose Luis Magana)dfWASHINGTON — The Federal Reserve left its key interest rate unchanged Wednesday despite persistently high inflation and a spike in energy prices caused by the Iran war. That caused the greatest disruption in oil supplies in history and sent energy prices surging. So-called core inflation — which excludes volatile food and energy prices — cooled in June, partly because apartment rents aren’t rising as fast as they had been. But several Fed policymakers have been arguing that the Fed will have to raise rates to return inflation to the 2% target.