President Donald Trump might not have understood the power discrepancy at play when he asked Ukraine's president to investigate Joe Biden and his son because he never served in the military, a Republican congressman suggested at the impeachment inquiry hearing on Tuesday.

Rep. Chris Stewart of Utah made the comment while questioning Lt. Col. Alex Vindman about his belief that Trump's request that Ukrainian President Volodymyr Zelenskiy do him a "favor" was actually a demand, given Ukraine's financial dependence on the United States.

"Your interpretation of the word 'favor,' and I'll paraphrase, feel free to correct me, you said in the military culture, which we're both familiar with, when a superior officer asks for a favor of a subordinate, they will interpret that as a demand. Is that a fair synopsis of what you've previously stated?" Stewart, an Air Force vet, asked Vindman.

"When a superior makes a request, that's an order," Vindman replied.

Stewart asked if that interpretation "is based on your military experience and the military culture."

"I think that is correct," Vindman said.

"I think that is correct," Stewart echoed. "Is President Trump a member of the military?"

"He is not," Vindman answered. Stewart noted that Zelenskiy is not a veteran either.

"Would it be fair then to take a person who has never served in the military and to take your re-evaluation of their words, based on your military experience and your military culture and to attach that culture and meaning of the words to someone who has never served?" Stewart asked.

"Representative, I made that judgment. I stick by that judgment," said Vindman, the National Security Council’s top expert on Ukraine. He was testifying alongside Jennifer Williams, an aide to Vice President Mike Pence, on the third day of the House Intelligence Committee’s public impeachment inquiry into the president.

Stewart then pulled a 180.

"I have to tell you, I think it's nonsense. Look, I was in the military. I could distinguish between a favor and an order and a demand. So could my subordinates. And I think President Zelenskiy did as well. He never initiated an investigation. In fact, he's been very clear. He said, 'I never felt any pressure,'" Stewart said.

Vindman said the context of the call, including an earlier demand for investigations, "made it clear that this was not simply a request."

"It's not clear at all," Stewart said.