Republican lawmakers cheered the strikes against Iran despite the president's campaign promises to keep the U.S. out of military entanglements abroad.

It's Trump's war now. The decision to bomb Iran showed the conflict between some of the president's fundamental impulses.

Dmitry Medvedev, the deputy chairman of Russia's Security Council, said on Sunday that U.S. President Donald Trump had started a new war for the U.S. by attacking Iran.