Inhofe, like other senators, zeroed in on Hagel's vote as a senator against labelling the Iranian Revolutionary Guard Corps a terrorist organisation and imposing sanctions against it.
Hagel said he was one of 22 senators who took the same position.
He was against the move because the US has "never, ever designated a part of a legitimate government, a state" as a terrorist organisation.
Hagel said the vote would have permitted the US to use force against Iran and America was already in two wars at the time. He noted that John Kerry, the new secretary of state, Joe Biden, now the vice-president, also voted against the measure in the Senate.
Hagel was pressed about his opposition to unilateral sanctions against Iran a decade ago, and said that was a different time. He said he regards Iran a state sponsor of terrorism.
Inhofe asked Hagel: "Why do you think the Iranian foreign ministry so strongly supports your nomination for secretary of defense?".
Exasperated, Hagel responded that he had no idea. "I have a difficult time enough with American politics," he said.
Several senators picked up on Hagel's statement in an interview for a book that the "Jewish lobby" intimidates many members of Congress. Hagel later apologised for using "Jewish lobby", saying he should have referred to "pro-Israel lobby".
Senator Roger Wicker pressed Hagel. "Do you stand by your statement they succeed in this town because of intimidation?" he said.
Hagel said he should have described it as influence not intimidation.
Senator Lindsey Graham picked up on the issue when he demanded that Hagel name any senator who has been "intimidated by the Israeli lobby" and identify a "dumb thing" Congress has been pressured to do by groups supportive of Israel. "I can't give you an example," said Hagel.
