U.S. Marine Corps Capt. Sean O’Brien, a native of Illinois, and the station ordnance officer for Marine Corps Air Station Iwakuni, poses for a photo at MCAS Iwakuni, Japan, May 2, 2024. O’Brien was born and raised in Glen Ellyn, Illinois and originally did not think of the military as the correct career path for himself. Now, with over 22 years of service, O’Brien has spent much of his time in the military carving new career paths, leading Marines and Sailors, and building a family.

U.S. Marine Corps Capt. Sean O’Brien, a native of Illinois, and the station ordnance officer for Marine Corps Air Station Iwakuni, poses for a photo at MCAS Iwakuni, Japan, May 2, 2024. O’Brien was born and raised in Glen Ellyn, Illinois and originally did not think of the military as the correct career path for himself. Now, with over 22 years of service, O’Brien has spent much of his time in the military carving new career paths, leading Marines and Sailors, and building a family.  (Photo by Cpl. Isaac Orozco)

MARINE CORPS AIR STATION IWAKUNI, Japan – Names are tremendously powerful. They represent culture, history, remembrance, and perhaps most importantly, family ties. A family’s name is one that connects each member of it to each other regardless of if they want to or not. Names can also command reverence if one’s bloodline is highly respected and or did good deeds, or perhaps the opposite if they didn’t. For better or worse, one’s name is partly what makes up one’s identity. However, that doesn’t mean someone’s image is left up to chance – far from it. People have the power to make a name for themselves in a different way, at least this is what has been instilled in U.S. Marine Corps Capt. Sean O’Brien. With 22 years of service across the world in both the enlisted and officer ranks, Capt. O’Brien, the station ordnance officer with Headquarters and Headquarters Squadron, Marine Corps Air Station Iwakuni, Japan, has learned throughout his career that being successful and building a good reputation for yourself isn’t a solo endeavor, rather, it’s one that impacts and requires the efforts of all of those around you.

“When I was on recruiting duty, I had a great Commanding Officer, Maj. Sean T. Quinlan, tell me once that you have three names: Your last name, your first name, and a third name, which is the name you make for yourself.” O’Brien said. “Your last name is your family name, their history – such as hailing from Ireland or Czechoslovakia – and what they did in the past. Your first name is your given name, even if it’s a messed-up name your parents gave you, it’s the one you got to live by. Finally, you have the name you make for yourself, which I think is most important. For example, what does it mean when someone comes to me and says, ‘Hey Capt. O’Brien, I need this done.’ Am I going to get the job done right? Do they already have that in their mind when they call for me? Do they think that I’m the guy that can make things happen?”

Growing up in Glen Ellyn, Illinois, O’Brien started life in the Chicago metropolitan area, in between the rural farmlands that comprise much of the Midwest and the controlled chaos of the big city. As a child, he had learned that his family history had been intertwined with the military throughout recent history.

“I come from a very strong military family,” O’Brien said “My dad was in the Army, got out as a sergeant and then went into the reserves. My grandpa was in Berlin after World War II during the occupation after the war was over. My other grandfather was a lieutenant commander, and I think he eventually became a commander in the Navy. My mom was in the Air Force for a couple of years as a corpsman, and my step-dad also in the Army. What’s interesting is that my uncle was the only one in the Marine Corps, and that was during Vietnam.”

Although his family was heavily tied to the military, it was not a driving force behind his enlistment. It didn’t even enter his mind until he was 21 years old. “What’s funny is I did not enlist because of them. In fact, I didn’t even think of the military when I was 18. I enlisted when I was 21.” O’Brien said. “When I was younger in the suburbs of Chicago, I was a package handler and then part time manager at FedEx. Later I was in carpentry as a rough framer doing whole subdivisions and townhouses. They were great jobs and I really enjoyed them, but since it was in Chicago, you’re scared about losing your job during wintertime because layoffs are coming in.”

Worries about uncontrollable job circumstances kept Capt. O’Brien working as hard as he could to keep his job, while at the same time leaving him wanting something more secure. He mulled over the idea of going back to school after he finished high school. Eventually, he had a series of conversations with one of his carpentry co-workers, a man named Joel, who eventually convinced him to take a chance and go back to school.

“Joel would talk for hours, you know, the whole day. Eight hours of me and him doing roofs from one house to another.” O’Brien said, “Joel was the guy who said, ‘Hey, you need to go back to school man, you should not be doing this.’ and I said, ‘Yeah, you know what? You’re right. I need to go back to school.’ But then there is the question of ‘How do I pay for school though?’ I call my mom and tell her, ‘Mom, guess what? I want to go back to school.’ She laughed at me. She said, ‘we tried this once, we’re not doing it again.’ I then said, ‘You’re right, you’re right, but still, how do I do this?’”

He remembered that joining the military would help immensely in paying for his schooling, and in August of 2001, O’Brien was already talking to a recruiter. By September 14th he had raised his right hand, just three days after 9/11.

“I never put two and two together. I did not think ‘Oh, 9/11 happened and now we’re going to war.’ Nobody really knew what was happening.” O’Brien said. “Everyone was gathering all this information and I never put the two together. I’m joining the military, and the United States was just attacked. At the time I was doing it because I wanted a job that I can sustain and go to school. I was a little naive about where they would send us.”

In January 2002, O’Brien shipped out to boot camp. He would make it roughly halfway through basic training before he would encounter tremendous adversity.

“Very early in my career, my dad passed away when I was in boot camp. That was very hard.” O’Brien said. “I got to go home on emergency leave in the middle of boot camp. That was a rough patch in my life. To be in the middle of week two of rifle training and lose your dad. Only to come back to training, change platoons, and be just as motivated as before you left. That was hard, but you learn from it, and you have to embrace it. After coming back, I knew what I wanted to do, and that was to not quit. I’m not going to quit because something terrible happens in my life. I’m going to set my mind forward and keep going.”

After basic training, O’Brien arrived at his first duty station at Marine Corps Air Station Yuma in November of 2002. Things were relatively normal until March of 2003, when the war in the Middle East continued to ramp up.

“March of 2003, that’s when everybody got kicked off the base. I was part of the remaining element, just luck of the draw I guess.” O’Brien said, “I think 10 of us really stayed back. All aircraft were gone except for around six of them. The whole MAG [Marine Aircraft Group] deployed, and here I am sitting at MALS [Marine Aviation Logistics Squadron] 13, waiting for everybody to get back.”

Soon after, O’Brien ended up deploying and supporting operation Phantom Fury from Al Asad Airbase in Iraq from July 2004 to November 2004 as a part of MALS-16. He would later return to Al-Asad on another deployment from February to September 2006, still part of MALS-16, in support of operation Iraqi Freedom.

After his deployments in the Middle East, O’Brien went on to recruiting duty in Des Moines, Iowa. He would find it time consuming, challenging, stressful, but immensely rewarding.

“I did recruiting duty for three years, and let me tell you, every day was a difficult day.” O’Brien said. “Even though it was difficult, nothing’s better than seeing kids that you enlist become successful Marines and bumping into them a couple of years later. Use the Marine Corps as a stepping-stone to get farther in life or use it to stay in and continue being successful. The Marine Corps is a tool to be successful in life no matter what you do. You learn from it and move on or stay in and keep going.”

After 12 years of being enlisted, O’Brien was eventually inspired to commission as an officer. Among his reasons was a desire to be more able to serve as a mentor to all his Marines, just like his leaders would do for him.

Now as the station ordnance officer of Marine Corps Air Station Iwakuni, Capt. O’Brien is responsible for all ordnance and other ammunition on MCAS Iwakuni.

“My team and I ensure that the ordnance that the squadrons want here is properly stored, segregated, and issued to the correct squadrons that are required to have it for training, operational activities, investments – whatever that requirement is. It’s everything from 9mm ammo for the pistol range all the way to air-to-ground missiles.”

As a leader of Marines, O’Brien has to be ready to answer any questions and all requests that come his way, especially those from Marines and Sailors under him. He believes that in order to get the most from his people, he needs to address why the mission they are executing is important in the first place.

“The most important thing for me is explaining the ‘why’ to my Marines and Sailors.” O’Brien said. “For example, when we shipped mortar rounds to Indonesia, MEF [Marine Expeditionary Force] asked us to support an ordnance movement, but the ordnance wasn’t here, it was in Sasebo. However, they knew we had a flightline and Sasebo didn’t, so we set it up at Iwakuni and flew it out here. It was very quick, within maybe a week or two to execute, but we got our ordnance up there. A couple weeks later, I saw on marines.mil that Indonesian Marines and U.S. Marines were training together doing 60mm mortars and something dawned on me. I said ‘That’s our ordnance. That’s our movement.’ That’s the ‘why’ right there. Why did we need to work longer hours that day? It’s because it was a crucial movement. I can just tell my Marines and Sailors ‘Hey, let’s pack it up and let’s ship it’ and once it flies, it’s gone, right? We’re done with it. But showing them the end result, showing the Marines training with that ordnance and what would happen if that shipment didn’t happen in time is the message. Could you imagine them trying to do the exercise without the mortars? It’s like going to the rifle range without rounds.”

In addition to the several unique experiences O’Brien has had throughout his career, he is also in a very fortunate position to have much of his family on base, a stark contrast to how he lived 20 years ago.

“I have a very unique family situation [here], as I got my son in law, my daughter, my son, my granddaughter, my wife, all here, so I got 75% of my immediate family together at the air station.” O’Brien said.

SSgt. Montrell Brunson, an aircraft maintenance data analyst with MALS-12, MAG-12, and the son-in-law of O’Brien, has also found the situation very beneficial, as having a strong connection to family so close to him makes life much smoother, especially on deployments.

“It really makes things a lot easier having someone close.” Brunson said. “Typically, you always hear that before you go on a deployment, make sure your home is good, but for me it’s already in good hands because I know when I leave, my family is taken care of. Dad, mom, or grandpa is here to take care of it on base if something’s up. That feeling that spouses or the family have of feeling alone, they don’t necessarily have in our situation, so I feel very fortunate.”

Brunson also says that even though O’Brien is an officer, it carries no odd interactions between them.

“He’s 100% approachable, it’s not strange at all.” Brunson said. “It helps that he’s been on both sides of the Marine Corps, the enlisted and the officer side. That carries with it a level of understanding that a lot of Marines don’t have.”

O’Brien has mutual feelings about the situation, especially looking back at how things used to be for him. He feels that although he faced complications through his career in the past, it’s thanks to both his families, his Marines and his literal family, that he’s able to handle the unexpected.

“The fun thing about us is we are lucky to have this opportunity to be with each other, to be able to lean on each other when life is sucky – sometimes in all aspects.” O’Brien said. “I’m very fortunate to not have too many adverse things happen in my life, partly because of me and partly because I had great NCOs [non-commissioned officers] and great Staff NCOs that always looked after me. I’ll tell you one thing: you show me Marines that have never been in trouble, and I’ll show you a Staff NCO or NCO that took care of them.”

Family, friends, and colleagues, all contribute to O’Brien’s success. It wasn’t what he originally envisioned as he was working odd jobs until his early twenties, but having a lengthy career in the Marine Corps has certainly made a name for him. As time has gone on, the uncertainty and anxiety have vanished, and all of his hard work and care for others have now paid off for him. O’Brien will continue to push forward, and for him, it’s all due to those that support him.

“The best success I had in my career is with that guy standing next to me, and it’s our success, not just my success.” O’Brien said. “It’s the team’s success. You’re successful as much as your team’s wrapped around you, and you better keep that nucleus tight. Keep Marines and Sailors around you successful too, and you can go anywhere and do anything.”

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