“When you have been ordered abroad on the command of the U.S. president, you think a lot about what’s at stake in that office, and there’s nothing more grave than the fact that that office holds the power to deploy troops into war zones,” said Buttigieg, a veteran of the war in Afghanistan. “I’m really concerned about the fact that right now, we’re seeing that power talked about in a very casual way.”

The mayor of South Bend, Indiana, was asked at his Fox News town hall under what circumstances would he as president approve the use of military force.

Pete Buttigieg said Sunday that he’s concerned about the Trump administration’s “saber-rattling” when it comes to other countries, notably Venezuela and Iran.

The Democrat mentioned the Trump administration’s “saber-rattling” with Venezuela and Iran, a term that equates to threatening military force. He said the situation in Venezuela is “horrible” but “not one where I see U.S. lives at risk.”

Buttigieg also said the U.S. tensions with Iran was “engineered” by John Bolton. He’s questioned the national security adviser before given Bolton’s past in pushing the U.S. into war with Iraq.

“How somebody who was behind one of the worst foreign policy mistakes in American history is allowed anywhere near the Situation Room of a president who claims ― really, falsely ― but claims that he was against the Iraq War all along, is unbelievable to me,” Buttigieg said.

The mayor said the next president will have two major jobs in terms of foreign policy: re-establishing U.S. credibility and setting a higher bar for deploying American soldiers abroad. He said that bar must be based on when “core U.S. life-or-death interests are at stake.”

“We do not send young men and women into war when there’s an alternative,” he said.

Buttigieg’s comments came the same day that President Donald Trump tweeted a threat against Iran, further escalating tensions.

“If Iran wants to fight, that will be the official end of Iran,” he wrote Sunday. “Never threaten the United States again!”

The president just days earlier avoided offering concrete answers on possible conflict with Iran, responding with “hope not” when reporters asked whether Washington would go to war.