Defense Secretary Lloyd Austin on Friday stressed the importance of public service during his commencement address to South Carolina State University, a historically Black college.

“Class of 2024, we need your service to the nation, so find ways to make change,” Austin told the graduating class of about 250. “To contribute. And to be a part of something bigger than yourself.”

Austin’s call to service comes amid a yearslong recruiting slump as the military service branches desperately try to fill the ranks. That difficulty in recruiting is due to a confluence of issues, such as young Americans struggling to meet the qualifications for service and low unemployment, but also because the military is grappling to figure out how to pitch service to Gen Z as it comes of age.

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Black Americans enlist in disproportionately high numbers, but Black troops are also less represented in the senior ranks. Austin has used his stature as the first Black defense secretary to speak directly to students about his own story and inspire them to public service, such as a similar speech he gave last year to graduates at Fayetteville State University near Fort Liberty, North Carolina.

On Friday, Austin, who grew up in Thomasville, Georgia, during the South’s Jim Crow era, said that in those “ugly days,” he was among the first Black teenagers to integrate into what was a whites-only school in Georgia.

“I doubt that the people trying to keep me out of that school imagined that they were blocking the education of a future four-star general and Cabinet official. We don’t have one American to spare,” he said. “We don’t have one citizen to squander. And that means that we need to keep working together to knock down barriers, to level the playing field, and to let everybody compete to win.”

Black recruits are overrepresented in the enlisted force, making up nearly one-quarter of new Army recruits in 2023, service data shows. Overall, Black Americans make up roughly 14% of the general population.

Meanwhile, only about 6% of top brass are Black officers across the military, according to data from the Carnegie Endowment for International Peace.

That has begun to change, at least at the highest echelons of the military. Austin rose to be a four-star Army general and the head of U.S. Central Command during a four-decade military career.

Austin now serves as the civilian leader of the Pentagon alongside Joint Chiefs Chairman Gen. Charles “C.Q.” Brown, who is also Black — the two highest military offices outside of the president.

Meanwhile, the services have made some progress in their recruiting efforts in recent years. But the Pentagon is having trouble finding applicants qualified for service, as defense officials estimate only 23% of young Americans can meet enlistment standards.

Those standards include being below a certain body fat percentage and passing the military’s SAT-style entrance exam, as well as scoring high enough to qualify for specific roles.

All of the services, as well as the secretary, have worked to portray military service as appealing to the youngest generation eligible for recruitment.

“Now, you’re graduating in challenging times. Divided times,” Austin said. “But so many things still bring us together as Americans. Our Constitution. Our democracy. The rule of law. The new Beyoncé album.”

Related: Austin Recounts Childhood Struggles with Racism in University Address Focused on Military Inclusion

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