Donald Trump projects strength as commander-in-chief, a role that allows him to start military operations while requiring he notify Congress within 48 hours — a notification he filed on March 2 in the case of the Iran conflict. But a second statutory deadline is looming: under the 1973 War Powers Resolution, a military operation may last only 60 days without congressional approval. That 60-day window expires on May 1. If Washington and Tehran have not negotiated a solution by then, the president must take further steps to legitimize continued US military action.
The War Powers Resolution was enacted to define how wartime authority is divided between the president and Congress. It reflects the founders’ intent that while the president is commander-in-chief, only Congress can declare war. The law requires the president to consult with Congress “in every possible instance” before introducing US forces into hostilities and to report to Congress when forces are committed. It was passed in 1973 as a lesson from Vietnam; President Richard Nixon vetoed it but Congress overrode the veto.
Although only Congress can declare war, formal declarations have been rare — the last congressional declaration was in June 1942. In practice, presidents have often relied on the War Powers Resolution’s ambiguous language or on other authorizations to justify military action, preserving executive flexibility while allowing some congressional oversight.
The law permits a one-time extension of the initial 60 days by an additional 30 days, typically to allow for an orderly withdrawal of forces. Stormy-Annika Mildner of the Aspen Institute Germany thinks this is the most likely route: Trump could claim progress toward a ceasefire and argue the extra 30 days are needed to finish winding down operations. That case would be harder to make if hostilities escalate, for example in the Strait of Hormuz, or if ceasefire violations are severe and persistent.
There is also precedent for a president arguing that the 60-day rule does not apply. In 2011, Barack Obama maintained that UN-authorized airstrikes in Libya did not trigger the War Powers Resolution because the operation did not involve sustained combat or sustained ground troops. The New York Times notes Trump could try a similar legal interpretation in the current situation.
Since early March, Congress has held five votes aiming to constrain the president’s actions; all failed, reflecting Republican control of both chambers, though some measures were close. Beyond symbolic resolutions, Congress has limited tools to end an operation. Cutting funding for the military would be effective in theory but politically fraught — starving troops of resources would have broad public and institutional backlash.
The looming 60-day deadline, however, could change dynamics. Some Republicans have signaled they might reconsider their positions. Utah Republican Rep. John Curtis stated plainly that he would not support continuing military action beyond the 60-day window without congressional approval. Still, experts see approval for continued action as unlikely: many Republicans prefer voting against measures to end the war rather than authorizing its continuation, since the latter would entail explicit responsibility for the costs, duration and risks — a politically risky stance with the midterm elections approaching.
Midterms on November 3 will contest all 435 House seats and 35 Senate seats. Polling suggests Republicans could lose majorities, and candidates in competitive districts are watching public opinion closely. Voting against Trump’s military action carries political risks for Republicans who may seek cover rather than confrontation with a president who has targeted party critics. At the same time, the war has driven up fuel prices and contributed to complaints about the cost of living, creating pressure within Trump’s base to de-escalate.
Given these dynamics, the president faces strong incentives to secure a face-saving resolution before the midterms, whether by using the extra 30-day withdrawal period, arguing the 60-day limit does not apply, or seeking a form of congressional authorization. How Congress responds after the May 1 deadline will shape the legal and political legitimacy of any continued US military action.
This article was originally written in German.