Trump's Iran Focus Deepens Economic Pain as Diesel Surges and Polls Slide

President Donald Trump's overall approval rating has dropped to the lowest level of his two terms in office, dragged down by public frustration with the ongoing war against Iran, sharply higher fuel costs and a growing sense that the economy is slipping out of control. The decline, measured in the latest CNBC All-America Economic Survey, comes as diesel prices have surged far faster than gasoline, threatening to raise the cost of nearly everything Americans buy and move.

The poll of 1,000 adults nationwide found just 40 percent of respondents approve of Trump's job performance, down five points from the previous quarter. Fifty-eight percent disapprove, pushing his net approval rating to negative 18, the worst reading since the survey began tracking him. The margin of error is plus or minus 3.1 percentage points. The fall is the steepest since public sentiment soured on Trump's handling of the coronavirus pandemic in 2020.

The numbers are particularly troubling for Republicans who face midterm elections in just over six months. Even within the president's own party, net approval among Republicans fell 17 points to its lowest level since 2017. While self-described MAGA voters remain fiercely loyal at 96 percent approval, support among non-MAGA Republicans dropped 19 points to 60 percent. The decline among independents and Democrats also reached record lows.

Public anger is focused on the economic consequences of the conflict that began Feb. 28. The war has disrupted global oil markets, but the pain is felt most acutely in diesel fuel, which powers the trucks that deliver goods across the country. Since the fighting started, the average price of diesel has jumped about 45 percent, compared with a 35 percent rise in regular gasoline, according to the Energy Information Administration. Diesel is now expected to peak above $5.80 a gallon this month, while gasoline averages around $4.30. The gap between the two fuels has widened because Persian Gulf production, heavily geared toward diesel and jet fuel, was cut sharply when the conflict began. Supplies were already tight beforehand, leaving no cushion.

The result is a slow-motion shock to the transportation industry. Trucking companies, farmers, construction firms and shippers are all facing higher operating costs that inevitably get passed on to consumers. Independent truckers, many of whom supported Trump in both 2016 and 2024, are among those feeling the squeeze most directly. The president has repeatedly downplayed the problem, recently telling reporters that gas prices are "not very high" despite AAA data showing them 27 percent above year-ago levels.

Trump's public focus has drifted elsewhere. Over a recent four-day stretch he used his Truth Social account to discuss a proposed triumphal arch, White House ballroom renovations, a UFC fight on the grounds, Bruce Springsteen's appearance and an AI-generated image of himself as Jesus. He also attacked the new Pope in unusually personal terms. Economic messaging has been sporadic and often disconnected from the figures Americans see at the pump and in grocery stores. Former Republican strategist Mike Murphy, co-host of the "Hacks on Tap" podcast, said the absence is striking. "Trump's original deal with the American people was 'I'm a boorish lout and kind of embarrassing, but I know how to run the economy.' And they believed that because they remember the economy being good in 2016."

Some voices in conservative circles argue Trump is simply following public opinion. Polls taken before and after the strikes on Iran showed broad concern about Tehran's nuclear program and deep antipathy toward the regime. Yet those same polls did not ask about the downstream economic costs that are now materializing. Republican pollster Micah Roberts, whose firm Public Opinion Strategies worked on the CNBC survey, sought to downplay the drop. He noted that 82 percent of Republicans still back the president and said a five-point decline during wartime and rising inflation "is not that big a move."

The administration has tried to pivot from military action to economic pressure. The Treasury Department has warned banks in the United Arab Emirates, Oman, China and Hong Kong against facilitating Iranian transactions. A military blockade in the Strait of Hormuz is meant to tighten the noose. But enforcement remains uneven. Turkey has emerged as a conspicuous weak point. Iranian-linked currency exchange houses in Istanbul and Ankara continue to move money for Tehran outside the formal banking system, bypassing SWIFT sanctions with minimal documentation. U.S. officials have sanctioned individual operators in the past, but the network persists.

The political danger for Trump and his party is that the economic fallout may outlast any perceived national-security gains. Diesel-dependent sectors are already warning of delayed shipments, higher retail prices and reduced investment. If those effects linger into the fall, the 2026 midterms could become a referendum on whether the administration's aggressive foreign policy has come at too high a cost for American households.

Trump built his political brand on the promise of a strong economy and toughness abroad. The latest polling suggests growing numbers of voters believe he is failing to deliver on the first while the second exacts an increasingly visible price. How the White House responds in the coming weeks, particularly whether it can bring fuel prices under control or at least convince voters it is trying, may determine if the current slide in support becomes a lasting political liability.