Eric Fanning, the first openly gay Secretary of the U.S. Army, served as a grand marshal at Saturday's San Diego Pride parade.

Fanning was nominated to the post in September by President Barack Obama and confirmed by the Senate in May.

Speaking Friday at a rally to remember Stonewall, the birthplace of the modern gay rights movement, Fanning hit back at critics of the 2011 repeal of “Don't Ask, Don't Tell,” which prohibited openly gay troops, and this year's end of the ban on transgender troops.

“Today, when our critics say that the military is not a place for social experimentation, they may be right,” Fanning said. “But equality and inclusivity are not experiments. They are American values.”

In remembering the 49 killed and dozens injured last month during a mass shooting at a gay nightclub in Orlando, Fanning said, “We should come together, even as we grieve and mourn. … Because we must respond to acts of cowardice with acts of confidence, with acts of pride in who we are and what we believe.”