President Donald Trump announced Saturday evening that the United States military carried out airstrikes on three Iranian nuclear sites, joining Israel’s bombing campaign in an effort to cripple Tehran’s ability to build a nuclear weapon.

After nearly two years of stark divisions over the war in Gaza and support for Israel, Democrats seemed at odds over policy toward Iran as progressives demanded unified opposition before President Donald Trump announced U.S. strikes against Tehran’s nuclear program. Party leaders were treading more cautiously.

While most congressional Republicans and some pro-Israel Democrats are praising President Trump's strikes on Iranian nuclear facilities, pockets of opposition are already emerging in both parties. Why it matters: The objections center on the argument that Trump needed congressional authorization for such a provocative use of military force,