The Senate voted 50-48 on Tuesday to approve a war powers resolution directing Trump to end military operations against Iran or seek explicit congressional authorization — the first time either chamber has passed such a measure against the Iran war. Four Republicans broke ranks with Trump to support it, signaling cracks in GOP unity on the conflict. The resolution is largely symbolic and doesn't carry full legal force, but it represents Congress asserting its constitutional authority over war powers for the first time since the Iran conflict escalated in February 2026.