The Senate passed a resolution forcing Trump to end military operations in Iran without congressional approval, a setback for the White House and a sign Republicans are splitting on the war.

• The vote was the eighth attempt since fighting began February 28; the war has now run 81 days, past the 60-day legal limit.
• Republican Bill Cassidy flipped to yes after losing his Louisiana primary, removing the political pressure that kept him in line.
• Three Republicans skipped the vote, including Cornyn, who is in a primary fight against Paxton, who just got Trump's endorsement.
• Trump won on a no-foreign-wars message, so this Iran turn is angering parts of his base and could hurt Republicans in the midterms and 2028.
• The resolution still needs to pass the House, where most members take money from pro-Israel groups, so final passage is unlikely.

Outlook: The resolution probably stalls in the House, but the Iran war will be a major issue in the 2028 race, with voters punishing whichever side misreads the mood.