The first five months of the Iran war have already drained U.S. taxpayers of about $38 billion, the nonpartisan Congressional Budget Office reports — a stark tally of how quickly extended military action eats into public funds as voters head toward November.

The CBO said Tuesday the conflict is now costing roughly $2 billion to $3 billion a month, consuming more than half of the Trump administration’s total war spending request so far. The agency also warned the campaign has depleted crucial U.S. weapons stockpiles, including interceptors used for air defenses.

The independent estimate — the most complete look yet at what the war means for taxpayers — will only intensify debate over whether continued military engagement serves America’s interests, and whether Washington should reconsider costly approaches that risk leaving the U.S. less prepared at home while other powers look for diplomatic openings.