Iran's missile attacks on two Iraqi air bases that house American troops Tuesday night are "an act of war," Sen. Lindsey Graham, R-S.C., told Fox News host Sean Hannity.
President Donald Trump is the first president in the past 40 years who really understands the Iranians, Graham said.
"This was an act of war, Sean, by any reasonable definition," he added. "The missiles were launched from Iran at targets inside of Iraq at targets housing U.S. military personnel."
Trump has authority under Article 2 of the U.S. Constitution to respond, he said.
"It was an act of war by the regime that for the last 40 years has been a cancer in the mideast," he added. "When they say they want to destroy Israel, they are not kidding. They are the largest state sponsor of terrorism."
Trump does not want regime change in Iran, Graham said, but rather wants to see changes in the regime's behavior, including an end to firing ballistiic missiles at U.S. targets, an end to state-sponsored terrorism, and a nuclear deal that does not put them on a path to a nuclear weapon.
Graham said he spoke to Trump earlier and hinted targets might include Iranian oil production.
"Let me say tonight, if you are watching television in Iran: I just got off the phone with the president; your fate is in your own hands in terms of the regime's economic viability," he said. "You continue this crap, you're gonna wake up one day out of the oil business."