I wish more boys and grown-ups could understand really what we’re doing 

here in Vietnam. When I get back I’ll try to define the meaning to other 

people that this war is not senseless and it has to be done no matter what 

the cost, as freedom has no price.

 Letter from Sgt. Robert Hrisoulis to parents

 19 January, 1971

Sgt Robert Hrisoulis was born in Detroit, Michigan on November 27, 1950. He 

attended Frank Cody High School in downtown Detroit, and soon after graduation in 1968, enlisted in the United 

States Marine Corps. After completing boot camp at Parris Island, he underwent advanced training to become 

a Special Radio Operator. As a cryptologic professional, Robert was responsible for providing and protecting 

critical communications to give his fellow Marines an advantage on the battlefield and to save lives. 

July of 1969 found him in Vietnam as part of the 1st Marine Division’s 1st Radio Battalion. The battalion had 

been “in country” since 1967, and during that time had provided critical combat support to a variety of tactical 

operations. Affectionately referred to as “The Greek” by his fellow Marines, Robert became a valued member of 

the unit, and quickly developed a reputation as highly skilled and motivated Marine. Prior to arriving in Quan Nam 

Province in January of 1971, he served at several duty stations, including Vandergrift Combat Base, Dong Ha 

Combat Base, and Firebase Fuller. By the time he headed off to Quan Nam, he was on his second tour. Robert 

arrived at his new assignment during the effort by the 1st Marines to implement “Operation Upshur Stream,” a 

preemptive search and destroy effort to prevent North Vietnamese forces from conducting rocket and artillery 

attacks on Da Nang. 

Starting on January 11, a series of units were airlifted from the basecamp to nearby Hill 383 to search for 

enemy units and weapons. They found nothing of worth from an intelligence or military perspective, but on the 

twentieth, four Marines fell prey to a booby trap. Additional casualties occurred when the rotor wash from the 

helicopter called in for medevac purposes set off a series of mines near the landing zone. Operation Upshur 

Stream had turned deadly.

On the twenty-first, Robert volunteered to go on a short courier run via helicopter to the staging base. Once 

there, however, he discovered he could be of use and decided to stay for the entire day and get a later flight 

back to his quarters. A fellow Marine remembers, “He (Robert) helped me re-string several antennas in the trees, 

took in the action... that was swirling around us, and wandered around taking pictures of our little outpost near 

the top of the mountain. Greek was going home in few days... I walked him down to the LZ at 

the end of day, and had the opportunity to say a goodbye that proved to be more final than 

either one of us intended. I was halfway back up the mountain when I heard the explosion. 

I turned to see smoke rising over a ridge further down the mountain. My heart was in my 

throat. I did not want to believe the worst.” Sadly and tragically, the CH-46A helicopter 

that carried Robert and 22 other Marines had crashed into the trees on its approach to the 

landing zone. Robert and four other Marines were killed. 17 others were seriously injured. 

THEY SERVED IN SILENCE

The Story of a Cryptologic Service and Sacrifice

Sgt Robert Hrisoulis, USMC
MP 33610

Two days before his untimely death, Robert wrote home to his parents. His thoughts were meant for them; 

however, his words not only describe his devotion to his work but also sum up why cryptologic professionals in 

harm’s way do what they do:

“I know you worry about me but please don’t because I’m alright. I’ll try not to take unnecessary chances because 

I have only 19 days more to go... the work I’ve been doing these past 18 months has been lifesaving to a lot of boys 

over here. I don’t mind working 18 and 20 hours a day because I feel I am saving many lives we...have Christmas 

to celebrate together for the first time in years.”

Robert was gone, but his memory lived on in the memories of his fellow Marines and family. 

Mike Summerson, who served with him, noted that “Bob excelled in everything that he undertook! I will never 

forget his motivation and wry humor. To my fallen friend who came into harm’s way just 2 weeks after I left 

country and just before he was supposed to leave. Always a Marine, Always remembered, Semper Fi!! Perhaps 

his father, George said it best, He (Robert) left us a lot of beautiful memories. He was a fine boy, and above all, a 

dedicated and good Marine.” 

For his courage and bravery on the day he died, Sgt. Robert Hrisoulis was posthumously awarded the Bronze 

Star. He is buried at Grand Lawn Cemetery in Detroit, Michigan.