Many of the social changes that have transformed the military under President Obama would be undone under a Trump administration, leaving some troops once again afraid to serve, according to one Navy vet.

Jim Lyons, who previously served in the Navy aboard two aircraft carriers, praised the courage of President Obama and Congress to repeal “Don’t Ask, Don’t Tell,” the law that prevented gay troops from serving openly. But he said he feels much of that hard work will be undone if the GOP nominee wins the White House.