President Donald Trump is struggling in the polls, and the economy sits at the center of his political troubles — though, as it turns out, not only because of inflation.

“Inflation, as measured by the Consumer Price Index, had fallen to about 3 percent when Mr. Trump returned to office, from a peak of 9 percent in 2022,” New York Times chief economics correspondent Ben Casselman wrote on Sunday. “Most economists expected it to drop further.”

The Consumer Price Index, a Labor Department gauge that tracks the average change in prices consumers pay for a basket of goods and services, is the government’s most closely watched inflation measure.

Casselman added: “Instead, progress stalled in 2025, partly because of Mr. Trump’s tariffs, which drove up prices of many imported goods. Then, just as the tariff effect was beginning to fade, Mr. Trump led the United States into war with Iran, which pushed energy prices and inflation back up. Consumer prices were up 3.7 percent in September from a year earlier.”

Michael Strain, an economist at the American Enterprise Institute, a conservative think tank, told Casselman that “voters had the sense that President Biden’s policies were leading to higher prices, and voters have the sense that President Trump’s policies are leading to higher prices now. In both cases, I think voters made the right judgment.”

“Gas prices are just the most visible piece of a broader affordability challenge,” Casselman wrote. “Record prices for diesel fuel are threatening to ripple through to food and other goods. The artificial intelligence boom has led to a surge in demand for computer chips and related equipment, which has raised costs for smartphones, tablets and other consumer electronics. And some economists say they believe companies are still waiting to pass along some of the cost of tariffs to customers.”

Diesel’s reach extends well beyond the pump: the fuel powers the trucks, trains, and farm equipment that move much of the nation’s food and freight.

Trade tensions with Canada have also contributed to recent price increases. The longtime American ally, responding to Trump’s rhetoric and trade practices, has imposed tariffs on a wide range of commonly consumed goods. The war with Iran has compounded inflationary pressures as well: Iran has retaliated by closing the Strait of Hormuz, driving up oil prices.

The strait, a narrow passage between Iran and Oman that carries roughly a fifth of the world’s oil, is considered the world’s most important oil transit chokepoint.

The administration’s framing of energy markets has drawn skepticism from economists, including over remarks by White House trade adviser Peter Navarro. “What Navarro said kind of demonstrates that he doesn’t understand markets,” Dr. Robert J. Shapiro, a former economic adviser to President Bill Clinton, told AlterNet in March. “If there is a risk premium, it’s only for oil futures — not for the price of oil today, not for the spot price — and then only when the risk is imminent. And so the price of oil rose by $10 in the runup to the launch of the war on Iran, which shows that it’s not baked in.”

Shapiro was drawing on a distinction traders rely on every day: spot prices reflect the cost of oil for immediate delivery, while futures prices embed expectations about supply and risk in the months ahead.

Laughing, Shapiro added: “These are commodities that are bought, sold and traded every day. They have a daily price, and the price reflects the supply and demand that day — and indeed in the morning, midday, afternoon or evening. So the notion that it was already built in is also clearly refuted by the fact that the price rose.”