To Justice Samuel A. Alito, – At oral argument, you asked about the necessity of efforts by the University of Texas to expand opportunity for students from all backgrounds: “Why is it important for the ROTC program for commissioned officers at Texas” — and indeed all ROTC colleges and universities — “to continue to consider race as one of many factors in admissions?”

We respectfully offer our reply.

A diverse military officer corps depends on the demographic composition of its primary sources, including ROTC, which provides almost half of the officer corps in the Army (the largest branch) and more than 40 percent of the Air Force’s officers.

As former military leaders, we understand that the Fisher v. University of Texas at Austin case isn’t only about equal opportunity — it’s about national security.

Restricting efforts to expand opportunities for admissions to the more than 1,000 ROTC-participating colleges and universities, including the University of Texas, would take dead aim at the diversity of the officer corps.

Diversity really matters. In the post-9/11 world, modern warfare requires a rich mix of skills and experience including foreign language skills, knowledge of other cultures and the ability to collaborate — and even culturally empathize with — different kinds of people. That is why the military must recruit more officers who reflect the diversity of our nation and the world with which we are engaged.

Therefore, the ROTC experience at Texas and other colleges and universities needs to be broadly diverse — and include individuals who have already shown an ability to lead in a multi-racial, integrated environment. That capacity to lead in a racially diverse setting is critical to effectively leading an increasingly diverse officer corps, as well as the enlisted ranks. And all students, and all members of the ROTC program, benefit from having those leaders among them — individuals, of all races and ethnicities, who can serve as bridges to cross-racial understanding.

Through extensive minority outreach and recruiting as well as limited consideration of race, the military has dramatically diversified the officer corps. Keys to this success have been the service academies and ROTC programs that prepare the next generation of military leadership. Thus, the percentage of minorities at the U.S. Military Academy at West Point has increased from 16 percent in the 1992-94 classes to 26 percent in the 2014-16 classes. Similarly, the most recent classes to enter the Naval Academy were the most racially diverse in history, with more than 28 percent minority enrollment. Meanwhile at the Air Force Academy, the Class of 2014 has 350 minority members — approximately 27.4 percent of the enrollees.

Much has been accomplished, but more remains to be done.

As the Military Leadership Diversity Commission recently reported, “Military officers today are less demographically diverse than both the enlisted troops they lead and the broader population they serve.”

A sweeping ruling by the court against using race as a factor in holistic review of each university applicant’s file would adversely affect attempts to achieve student body diversity at all universities with similar admissions policies and with ROTC programs — and the military academies as well. This would make it more difficult to prepare highly qualified minority officers, as well as officers from every background who have had the benefit of being educated in the diverse environment which our modern military leadership demands.

Remember: Unlike many other institutions, the military operates on a closed personnel system; its top leaders are chosen not from outside but rather promoted from lower ranks. While an auto company can appoint an aerospace executive as its CEO, the Navy can’t select admirals who have never served at sea.

Make no mistake: The military needs leaders from every background whose education in colleges and universities with diverse student bodies prepares them to deal with people from different cultures and outlooks — so that they can sustain coalitions, lead multi-national missions, and deepen effective relations with friends and allies around the globe.

Promoting equal opportunity is a lofty goal for our nation’s colleges and universities. But, for the U.S. military, a highly qualified and racially diverse officer corps is a mission-critical national interest. The stakes — our national security — could not be higher.

By retired Lt. Gen. Dan Christman, superintendent of the U.S. Military Academy at West Point from 1996 to 2001; retired Lt. Gen. John F. Regni, superintendent of the U.S. Air Force Academy from 2004 to 2005; and retired Vice Admiral John R. Ryan, superintendent of the U.S. Naval Academy from 1998 to 2002.