While Memorial Day heralds the start of summer, we must not forget this holiday’s true purpose — to remind us of the ultimate sacrifice made by brave men and women who died safeguarding our freedoms.

In my 32 years in the U.S. Air Force, I knew members in all branches of the Armed Forces who died serving their country.

At The Citadel we commend those graduates of the Long Gray Line who have served in the military and those who gave, as Lincoln said, “the last full measure of devotion,” in all American conflicts since the Mexican-American War. In the current war on terror, 18 Citadel graduates have given their lives to their country.

Marine 1st Lt. Therrel Shane Childers, class of 2001, 30 years old, was the first American casualty of Operation Iraqi Freedom. He died leading a platoon capturing the Ramallah oil fields.

Army Sgt. Aaron X. Wittman, ’07, 28 years old, was our most recent loss. He was the first American casualty of 2013, struck down while on mounted patrol and on his second deployment, having already been awarded a Bronze Star and Purple Heart.

Sgt. Wittman’s family has contributed his ring to The Citadel Alumni Association’s “Band of Gold” program. Aaron’s ring will be melted down and included in the gold used to cast the rings for the Class of 2014. His courage and leadership will touch every cadet who receives a ring this October.

Just a few weeks ago, we celebrated the graduation of the Class of 2013.

I am very proud that this year almost 40 percent of these young men and women accepted commissions as officers in the Army, Navy, Marines, and Air Force. They took on the responsibility of leading other men and women, possibly into harm’s way, so that we may live in a free country.

So on this Memorial Day please remember in your thoughts and prayers the brave service men and women who have died in the line of duty and their families who supported their decision to serve our country.

Today, we remember:

Lt. Col. Chad Buehring (U.S. Army), Citadel Class of 1985, killed in Iraq on Oct. 26, 2003; Master Sgt. Robert V. Derenda (U.S. Army), Class of 1985, Iraq, Aug. 5, 2005; Officer Arsenio Domingo (international police liaison officer), Class of 1987, Iraq, Jan. 7, 2006; Capt. Christopher Kenny (U.S. Army), Class of 1993, Iraq, May 3, 2004;

Capt. Benjamin Sammis (U.S. Marine Corps), Class of 1996, Iraq, April 5, 2003; Capt. Daniel W. Eggers (U.S. Army), Class of 1997, Afghanistan, May 29, 2004; Maj. Brian Michael Mescall (U.S. Army), Class of 1997, Afghanistan, Jan. 9, 2009; Lt.j.g. Peter Ober (U.S. Navy), Class of 1998, Sicily, July 16, 2003;

1st Lt. Therrel Shane Childers (U.S. Marine Corps), Class of 2001, Iraq, March 21, 2003; 1st Lt. Dan Thomas Malcom (U.S. Marine Corps), Class of 2001, Iraq, Nov. 10, 2004; 1st Lt. Almar Fitzgerald (U.S. Marine Corps), Class of 2004, Iraq, Feb. 21, 2006; Capt. Warren A. Frank (U.S. Marine Corps), Class of 2004, Iraq, Nov. 25, 2008;

Capt. Ryan Hall (U.S. Air Force), Class of 2004, Djibouti, Feb. 18, 2012; 1st Lt. Ryan Rawl (S.C. National Guard), Class of 2004, Afghanistan, June 20, 2012; 1st Lt. Joshua Booth (U.S. Marine Corps), Class of 2005, Iraq, Oct. 17, 2006;

Lance Cpl. Timothy Creager (U.S. Marine Corps), Class of 2005, Iraq, July 1, 2004; Sgt. Aaron X. Wittman (U.S. Army), Class of 2007, Afghanistan, Jan. 10, 2013; Lance Cpl. Jonathan A. Taylor (U.S. Marine Corps), Class of 2009, Afghanistan, Dec. 1, 2009.

Lt. Gen. John W. Rosa, USAF (retired), Citadel Class of 1973, is president of The Citadel.