How could the new US Congress bring about an end to the war with Iran? - explainer

As the new US Congress takes office, lawmakers are exploring ways to bring an end to the ongoing war in Iran. While the president and Republicans in Congress remain steadfast in their support for the conflict, Democrats have vowed to push for legislation that would prohibit funding for the war.

Congress cannot unilaterally end the war, but it can pressure the president to do so. One way lawmakers can do this is by using their control over federal funding. The current defense budget, which has been increased by Trump to $1.5 trillion, is likely to face opposition from Democrats who are unwilling to approve such a substantial increase. Democrats have proposed cutting off funding for the war before Congress even convenes, in the hope that anti-war Republicans or those concerned about the deficit will back them.

A government funding bill is set to expire on December 11, meaning Congress must pass a full-year budget or a short-term spending plan to avoid a shutdown before Christmas. Democrats could include clauses in budget bills that forbid the use of funds for hostilities against Iran, forcing Trump to either veto the bill or risk a government shutdown and the potential loss of pay for troops.

Another avenue for Congress to pressure the president is through the National Defense Authorization Act (NDAA). This annual bill sets policy for the Pentagon, and if Democrats refuse to authorize any funding for the war, it could be an embarrassment for both parties.

Legislative resolutions on war powers are another tool at Congress' disposal. Trump did not secure approval from Congress before launching the war, and Democrats have repeatedly voted to end the fighting unless he seeks authorization. While Trump's administration has ignored these resolutions, Democrats plan to keep pushing for more war powers resolutions and legislation.

Oversight of the Trump administration is also a potential avenue for Congress to bring the war to an end. Democrats have attempted to impeach Defense Secretary Pete Hegseth on charges of waging the Iran war without congressional approval, but the effort failed. However, Democrats may try again next year, viewing Hegseth as the individual most responsible for the war.

Once they take control of congressional committees, Democrats can hold hearings and launch investigations into the administration's strategy, spending, and conduct of the war, including issuing subpoenas to compel testimony.