WASHINGTON — Confronted by an intransigent Iranian government that has refused to back down in the face of a massive military campaign, President Donald Trump appears to have settled on a dual-prong approach that combines economic pressure with the potential of a devastating escalation in force . Having launched “Operation Economic Outcast” just last week to try to isolate Iran from its remaining global trade partners , the Trump administration also resumed strikes in recent days, prompting Iranian retaliation that has renewed concerns of an all-out regional war. However, the combination of already intense sanctions on Iran and an off-and-on bombing campaign since the war began more than six months ago has not bowed the Iranian leadership and has left the administration struggling to find a way to wind down the conflict . Tehran has dug in its heels — to Trump’s frustration — as energy prices rise, the global economy roils and poll numbers on the administration's handling of the war dip ahead of November’s midterm congressional elections. Trump said Wednesday that he didn'