Three ways the new Congress can stop Trump’s war The “Blue Wave” that swept Democrats to victory in Tuesday’s midterm elections was powered by public opposition to President Trump’s disastrous war of choice with Iran. In exit polls, 74 percent of voters said the Iran war was a crucial or major factor in their vote.

Seven in 10 voters want Congress to prioritize ending that war, which it never authorized.

Even with healthy majorities in both chambers, making good on that mandate won’t be easy. After all, a congressional majority has already voted to stop this war: in June, both houses directed the president to withdraw U.S. troops from hostilities, yet here we are.

Even so, the incoming Congress has several constitutional tools to push Trump toward ending the war. Let me name just three.

First, Congress can refuse to fund the war. The most effective leverage Congress has capitalizes on what it usually does best: nothing. It doesn’t take a supermajority to defund a war; all it takes is for one chamber of Congress to refuse to pay.

The Trump administration has spent nearly $50 billion on “Operation Epic Fury” so far, even though Congress has yet to pass specific appropriations for it. But in a conflict this expensive, creative accounting only goes so far. Facing “an urgent budget shortfall” this summer, the administration requested Iran war funds; that request now sits with the Senate, which can tighten the squeeze just by letting it sit.

The power of the purse has historically been Congress’s “most effective way” to force presidents to change course, the Congressional Research Service notes. But maximizing that leverage requires more than simply standing pat.

During the Nixon administration, a resurgent Congress used appropriations riders to help wind down the Vietnam War, imposing a hard cutoff on combat operations in Southeast Asia after Aug. 15, 1973. Twenty years later, after Black Hawk Down, similar tactics helped end our nation-building excursion in Somalia.

The 120th Congress can follow the same playbook: conditioning funding on withdrawal by a date certain.

Second, Congress can impeach Trump’s Defense secretary, reinvigorating a constitutional weapon dulled by the Trump era. In mid-September, Speaker Mike Johnson (R-La.) rushed the House to early recess to avoid a vote on impeaching Defense Secretary Pete Hegseth. The articles, drawn up by Rep. Thomas Massie (R-Ky.), are coming right back: the Republican gadfly intends to force a vote this week when the House returns.

Four of the eight articles in Massie’s bill of particulars center on Iran: that he is carrying out an illegal war in violation of the Constitution’s Declare War clause and multiple provisions of the 1973 War Powers Resolution.

Amid a deeply unpopular war, constitutional censure by the House could really leave a mark. True, Trump could moot the effort by firing Hegseth. But either way, the goal shouldn’t be simply getting a scalp, but imposing costs for continuing an unnecessary, unconstitutional war.

Third, the new majority can bring in the courts. The first branch can enlist the help of the third, the federal judiciary.

In July, after Trump blew past the War Powers Resolution’s time limits and the resolution directing him to withdraw, Rep. Gregory Meeks (D-N.Y.) moved to enforce the law in court. Under Meeks’s bill, the House would sue the president, with Johnson dragooned into the role of lead plaintiff (no doubt apologizing to Trump the whole way).

Article III courts are ordinarily loath to intervene in war powers fights between the political branches. Past attempts by House members to sue presidents over unauthorized warmaking have been bounced for lack of standing.

But when the House as an institution files suit, the case has a much better shot at getting heard. In 2020, when the House sued Trump for illegally diverting funds to his border-wall project, the D.C. Circuit granted standing because Trump’s gambit had effectively “snatched the House’s key out of its hands.”Johnson may be able to put off the suit, but in January, Rep. Hakeem Jeffries (D-N.Y.) gets the Speaker’s gavel and the House can take Trump to court.

Would a federal court declare the war illegal? That’s unlikely. But, win or lose, both Meeks’s lawsuit and Massie’s impeachment drive will keep the war and the constitutional arguments against it in the front of the public mind.

Survey experiments by political scientist Douglas L. Kriner indicate that congressional opposition to war framed in constitutional terms is especially persuasive because “most Americans, like the Framers, still desire collective judgment in questions of war and peace.”Meanwhile, Congress can keep the pressure on by wielding its most powerful weapon: the power of the purse.

Congress doesn’t need new powers or bigger majorities to fulfill its constitutional responsibilities and bring an end to an illegal war, it needs to start using the powers it has. Gene Healy is a senior scholar at the Reason Foundation and author of “The Cult of the Presidency.”