He spoke of “overwhelming force” and the U.S. military’s unmatched ability to rain “death and destruction from above” on its “apocalyptic” Iranian foes.

Then, Defense Secretary Pete Hegseth, standing in the Pentagon, issued a call to the American people for a specific kind of wartime prayer. He asked them to pray for victory in battle and the safety of their troops.

“Every day, on bended knee, with your family, in your schools, in your churches,” he said, “in the name of Jesus Christ.”

At a time when the U.S. and Israeli militaries are dropping thousands of bombs on a majority-Shiite Muslim nation, the explicitly Christian nature of Mr. Hegseth’s call stood out.

More than any top American military leader in recent history, Mr. Hegseth has framed U.S. military operations in the Middle East, Africa and Latin America as bigger than politics or foreign policy. Often he has imbued these actions with a Christian moral underpinning that suggests they are divinely sanctioned.

It is this view of a higher power, married to lethal American firepower, that Mr. Hegseth says gives him confidence that the United States will prevail in Iran.