The Senate voted 50 to 47 to advance a resolution forcing President Trump to end hostilities in Iran or seek congressional authorization. Bill Cassidy of Louisiana, who lost his primary after Trump targeted him, joined three other Republicans in supporting the measure. This marks the eighth attempt by Democrats and allies to rein in Trump's military campaign, now in its third month.

Cassidy cited the administration's secrecy around Operation Epic Fury, stating Congress remained 'in the dark.' His defection, following a primary loss, signals growing Republican unease with Trump's handling of the conflict and refusal to engage Congress. Senators Lisa Murkowski and Susan Collins also broke ranks, while John Fetterman was the lone Democrat voting no.

Even if passed by both chambers, a presidential veto is assured. The political standoff coincides with shaky cease-fire talks and Iranian blockades of the Strait of Hormuz, which have driven up global oil prices. Lawmakers face constituent anger over energy costs, adding pressure as the Memorial Day recess approaches.