During the presidential campaign, President-elect Donald Trump called the Obama administration’s move to open combat fighting roles to women in the military “politically correct” and said he might reverse the policy. On Monday, the woman who might have been Hillary Clinton’s defense secretary called on him to preserve options for women who serve in uniform.

“If we reverse direction, it will very likely have very profound impacts — certainly for morale, certainly for retention of women who are looking for opportunities … and it will probably also impact recruiting,” Michèle Flournoy, who served as undersecretary of defense for policy during President Obama’s first term, said Monday at an event at the Aspen Institute.

Trump has said he would follow the recommendations of military leaders on a range of military personnel policies. But it’s not clear what this will mean for last December’s decision to open up all combat roles to women who meet fixed standards and last July’s move to allow transgender soldiers to serve openly and receive related medical coverage.

“We have a politically correct military, and it’s getting more and more politically correct every day,” Trump said at a campaign event in October. “Some of the things that they’re asking you to do and be politically correct about are ridiculous.”

In September, Trump defended a 2013 tweet in which he seemed to blame gender integration in the military for a rise in sexual assaults. “26,000 unreported sexual assaults in the military — only 238 convictions. What did these geniuses expect when they put men & women together?” Trump tweeted.

Flournoy, who was widely expected to be named as the first female defense secretary if Clinton had won, said the Trump team should look at all of the research, develop a deeper understanding of the issue and then make decisions based on what the actual implications would be of rolling back military personnel reforms, rather than treating it as a political issue.

“I would hope the new administration would take a fact-based, data-informed approach to this issue, understand it for all of its potential implications and ultimately choose to stay on the trajectory that’s been set by a couple of administrations now,” she said.

Setting standards and then allowing members of the military to try to meet those standards regardless of gender or gender identity is the right approach socially and militarily, she argued.

“Ultimately, having a military that is a truly a meritocracy, that has the diversity that looks like America, that leverages all our strengths across the full range of human capital and people who are willing to serve, that’s in our interest as a nation,” she said.

If Trump does decide the new policy based on the views of the uniformed military leadership, the current reforms could very well be reversed. According to reports, the current chairman of the Joint Chiefs of Staff, Gen. Joseph Dunford, opposed the decision to allow women to serve in combat roles and tried to exempt his service, the Marine Corps, from the policy.

The GOP platform explicitly calls for keeping women out of combat units and infantry battalions and proposes a review of the Obama administration’s “ideology based personnel policies.”

“We reject the use of the military as a platform for social experimentation and will not accept or continue attempts to undermine military priorities and mission readiness,” the platform states. “Military readiness should not be sacrificed on the altar of political correctness.”

The incoming Trump administration is pledging to strengthen and expand the size of the U.S. military, but it risks weakening that very effort by pushing away women who want to fight.