(NewsNation) — President-elect Donald Trump has nominated Fox News commentator Pete Hegseth for Secretary of Defense, sparking controversy over Hegseth’s experience and his comments about women in combat.

The Defense Secretary nominee has said he doesn’t believe women should serve on the front lines in combat roles, raising the possibility he could try to roll back policies that allow women in those jobs.

Former U.S. Army Sgt. Kayla Williams served on the front lines in Iraq as a linguist. She told NewsNation that at the time, women were limited in terms of combat roles, which made her work more challenging.

“We know that what really didn’t work was to not have women directly assigned to these units, to have women like me just be attached so we hadn’t trained as we fought,” she said. “I didn’t know their standard operating procedures. Those programs that had to be stood up like the cultural support teams to fill that gap were just inadequate.”

Williams said it is essential that women be able to join the military in all aspects, especially when the service is facing a recruiting shortage.

Former U.S. Army Maj. Chase Spears disagrees, saying that while women have proven they can meet the physical standards required for combat roles, they are built differently and still shouldn’t be eligible to fill those positions.

“The question is, can women endure the standard day after day, week after week, month after month,” Spears said.

Spears claimed women do poorly in combat roles and said inclusion hasn’t made the military more lethal.

Williams noted that while women may not always be as strong as men, they bring different skills to the table that can also be critical, like agility.

“We know from examples like the woman recently completing the Appalachian Trail many, many hours faster than anyone else ever has, that women have real advantages when it comes to endurance,” she said.