Congress can’t stop Trump’s wars. It can make them expensive.

Democrats now control both chambers, but the president still holds the commanding heights of foreign policy. The change will come in cost and tempo, not direction.

Capitals from Tehran to Tallinn are reading Tuesday’s results as a verdict. Democrats won both houses of Congress. The war in Iran helped drive the result, and Donald Trump himself conceded afterwards that it had played a part in his party’s defeat, even as he defended launching it. Voters had endured eight months of conflict that pushed up petrol prices and dragged down the president’s approval ratings. Election 2026: Democrats capture both chambers of Congress

It is tempting to conclude that American strategy is about to bend. It is not. The election has changed what the president’s choices cost, and he can still make them.

The sole organ

Lawyers like to quote a 1936 Supreme Court opinion calling the president the “sole organ” of the nation in foreign affairs. The line is over-read: the Constitution gives Congress the power to declare war and to fund armies, and the court itself later reined in presidential claims in the Youngstown steel-seizure case. But the practical record favours the executive. Sanctions, strikes, deployments, executive orders and the daily management of alliances all sit within the president’s reach, and Congress has rarely found a way to take them back.

The current war shows how little a hostile legislature can do on its own. The House has repeatedly passed resolutions to limit operations against Iran, and the Senate approved its own version in June. A later Senate attempt fell short by a single vote, and a House measure passed 220–204 in September with seven Republicans joining Democrats. None of it has changed the facts on the ground. Mr Trump has shown more than once that he can veto such resolutions or simply ignore them, and Democrats lack the two-thirds majority needed to override a veto. democrats projected win house voters rebuke trumps iran war

Where the pressure bites

The Democrats’ real leverage is the budget. Before the election, senior Democrats promised to cut funding for the Iran war if they won power. Senator Tim Kaine has argued that, with war-powers votes ignored, his party is “pushed back to the appropriations side” and has floated amending the War Powers Act so that funding for unilateral operations lapses automatically after 60 days. This is a blunt tool. Spending bills need bipartisan support in the Senate, and a Congress that is seen to starve troops in the field pays a political price of its own. But the threat alone changes the president’s calculations. Where Democrats Can Thwart Trump’s Foreign Policy

Oversight is the second lever. Committee chairs can investigate how the administration makes foreign-policy decisions even where they cannot reverse them, and subpoenas and televised hearings turn a quiet policy into a daily argument. Personnel is the third: ambassadorships and other nominations give the Senate a way to extract concessions.

The pattern is familiar. Congress cannot command the president, but it can raise the price of every decision he takes. As the commentator Anne Applebaum put it, it can offer a different narrative about the war and about American foreign policy more broadly.

The danger of a cornered president

The counterintuitive risk is that political weakness at home makes unilateral action abroad more tempting. Before the election, Mr Trump hinted several times that hostilities with Iran would resume afterwards, and one analyst argues he was held back by the campaign and no longer is. Another warns that a president who feels cornered may choose to use force unilaterally. A new Congress is not sworn in until January, and Mr Trump says little will change in the lame-duck session. That leaves a window in which the executive faces no new constraint. will democratic control of Congress change Trump’s Middle East policy 3006125

Adversaries will also read the ballot box for weakness. Tehran may conclude that American resolve is eroding. Washington’s task is to pair any diplomatic opening with deterrence that adversaries believe, which is much harder when the opposition party is publicly calling for the war to end.

What will not move

Most of American strategy is untouched by an election. Freedom of navigation in the Strait of Hormuz and the Bab el-Mandeb, the commitments in the Indo-Pacific, the nuclear red lines on Iran and the weight of NATO are held in place by forward bases, treaties and a national-security bureaucracy that outlasts any Congress. Allies may feel some renewed confidence in American democracy, but confidence is not policy. Even Democrats who want to rein in the war have not, so far, proposed abandoning the Gulf.

What to watch

Three tests will show whether this is a shift in cost or something larger. The first is the January spending fight, when Democrats must decide whether to use the purse to constrain operations. The second is whether the seven House Republicans who defected in September become a bloc or remain a footnote. The third is the first round of Iran hearings. If witnesses are forced to defend the war under oath, a president who has governed by decree will have to start justifying his choices.

Foreign policy will not pivot. But for the first time in two years, it will have an audience that talks back.