Americans voted against the Iran war, and now a new Democratic Congress has the constitutional power to strangle its funding — but don't hold your breath waiting for the swamp to actually do it.

The eight-month war that President Trump launched alongside Israel on February 28 without congressional approval helped cost Republicans their majorities last week. Trump himself acknowledged that public anger over the conflict contributed to his party's losses, though he insists both that he has won the war and that it will continue. A Reuters/Ipsos poll this month found 71% of Americans — including 93% of Democrats and 51% of Republicans — want Congress to pass legislation ending the conflict. The Guardian reported that Republicans lost young white men badly in the midterms, with only 43% voting for a GOP House candidate, down from 63% in 2024. The public mood shifted as the wars in Gaza and Iran dragged on.

Here is what Congress can actually do. Under the Constitution, Congress controls the purse. Trump has requested a massive defense budget hike — from roughly $950 billion to $1.5 trillion, plus an additional $67 billion for the Iran war. Democrats say they won't approve it. They've also proposed cutting off war funding before the new Congress is even seated, hoping anti-war Republicans or fiscal hawks might join them.

The current government funding bill expires December 11. House Republican leaders say they'll hold the line. Representative Tom Cole of Oklahoma, who chairs the House Appropriations Committee, told reporters this week: "A Republican Congress is not going to send bills to a Republican president that he's going to veto, so if that's their demand, well, we'll just wait until next year."

Once Democrats take over, they can embed provisions in spending bills prohibiting any funds from being used for hostilities against Iran. Trump could veto those bills, but that means risking a government shutdown — and potentially no pay for the troops — to keep the war going. Congress can also refuse to authorize war funding in the annual National Defense Authorization Act. The NDAA has passed every year since 1961; its failure would embarrass both parties.

Then there's the war powers route. Democrats and a handful of Republicans have already voted repeatedly to end the fighting unless Trump seeks congressional authorization. One war powers resolution passed both chambers, but the Trump administration ignored it, and legal experts told Al-Monitor there is no consensus on whether it was binding. More votes are coming. But Trump is expected to veto any measure that stops the fighting, and overriding a veto requires two-thirds in both chambers — meaning Democrats need Republican votes.

The backers say it's worth trying anyway, to send a message. But sending messages is what Washington does instead of acting. The money is the lever. The NDAA is the lever. A shutdown threat is the lever. Every one of those tools requires Democrats to pick a fight with a president who doesn't blink — and to find Republicans willing to break ranks.

The American people didn't vote for another Middle Eastern entanglement. The question now is whether the new Congress will honor that or just find new ways to keep the checks flowing.