Senate rejects war powers measure as key Republicans reverse course on Trump's Iran strategy

The Senate rejected a war powers resolution Wednesday night aimed at restricting President Trump's military authority against Iran, in a 50-47 procedural vote that marked a reversal from the previous day's narrow passage of a similar House measure. The vote came after Trump expressed frustration with Republicans supporting the measures, arguing that congressional rebukes had undermined his negotiating position with Iran.

Two prominent Republican senators who had previously supported Iran war powers restrictions changed their positions. Senator Rand Paul of Kentucky voted present instead of yes, stating that while his views on war powers remained unchanged, he wanted to give Trump "more space and leverage to negotiate a lasting peace" after the president requested consideration of his negotiating position. Senator Bill Cassidy of Louisiana, who had voted in favor of Tuesday's resolution, voted against advancing Wednesday's measure after receiving what he described as a "thorough briefing" from Vice President JD Vance and special envoy Steve Witkoff.

The shift followed a tense Senate GOP lunch where Trump directly confronted Cassidy over his earlier support for the resolution. According to Cassidy, Trump "raised his voice" during the meeting, and Cassidy said he "lost my temper." Earlier, Cassidy had defended his position to reporters, stating: "You have not told the American people what's going on. It was supposed to last four weeks, it's lasted four months. Our original objectives have not been achieved."

Senators Susan Collins of Maine and Lisa Murkowski of Alaska were the only Republicans voting to advance the Kaine resolution, joining most Democrats. Democratic Senator John Fetterman of Pennsylvania voted against it. The procedural motion's failure prevented the measure from moving forward, despite the Senate's passage Tuesday of a similar House-passed concurrent resolution on a 50-48 vote, which does not require presidential signature.

The Kaine resolution would have directed Trump to remove U.S. Armed Forces from hostilities with Iran unless Congress authorized continued military action. However, Trump administration officials have argued the U.S. is no longer engaged in active hostilities following the ceasefire agreement, and have contended that the 1973 War Powers Resolution itself is unconstitutional. Wednesday's vote marked the 11th Senate vote on an Iran war powers measure since the beginning of 2026. Trump has publicly welcomed the Senate's rejection, posting on Truth Social that the vote "puts Iran on notice."