Combined Action Platoon (CAP), Vietnam —Part I

CAP BadgeThe Combined Action Program was a United States Marine Corps operational initiative implemented in the Vietnam War; it proved to be one of the most effective counterinsurgency tools developed during that conflict. The concept, however, seems to have at least partially originated with pacification programs in the Philippines, Haiti, Nicaragua, and the Dominican Republic during the so-called Banana Wars in the late 19th and early 20th centuries. The Marine Corps never throws any previous doctrine away.

“In small wars, tolerance, sympathy, and kindness should be the keynote of our relationship with the mass of the population … The purpose should always be to restore normal government … and to establish peace, order, and security.”

—Small Wars Manual, 1940

In Vietnam, the CAP operated from 1965 to 1971. The program was characterized by the placement of a thirteen-member Marine rifle squad, augmented by a U.S. Navy Corpsman and strengthened by a Vietnamese militia platoon (called Popular Forces, or PFs) of older youth and elderly men within or adjacent to rural Vietnamese hamlets. In most cases, the PFs were residents of the hamlet; they were either too old, or too young for conscription into the Army of the Republic of Vietnam (ARVN) units. Together, Marines, Navy personnel, and PFs were designated a Combine Action Platoon.

In terms of the CAP mission, Marines and local Vietnamese cooperated with one another to protect and secure the hamlet from enemy infiltration. The placement of these small units expanded the tactical areas of responsibility (TAOR) of Marine Corps infantry battalions in that region. In this series we have the first hand account of a Marine who commanded a Combined Action Platoon in Vietnam. Long after retirement, he subsequently prepared a comprehensive list of “lessons learned” used to reinstitute the CAP in both Iraq and Afghanistan.

By the time William C. Curtis arrived in Vietnam, he had already completed seven years of active duty. Enlisting in the Marine Corps in 1958, Curtis was selected for sea duty. He served two years aboard the USS Hornet (CVS 12) as both Admirals’ orderly and as an NCO of the ship’s guard. Subsequently, Curtis was assigned to the Regimental Guard while assigned to the 1st Force Service Regiment at Camp Pendleton. During his next enlistment, Curtis successfully graduated from Marine Security Guard School, augmented US Secret Service missions on behalf of President John F. Kennedy, and served at both the US Embassy Rome, and in Oslo, Norway.

Curtis left the Marine Corps after his second enlistment, but applied for and was accepted into the Marine Corps Platoon Leader’s Class —a program that would ultimately result in a commission to second lieutenant at the end of his college education. Within a few weeks of his discharge, however, in March 1965, the Ninth Marine Amphibious Brigade (9th MAB) made an amphibious landing at Da Nang, Republic of Vietnam. The more Curtis watched these events unfold, the more he regretted having accepted his separation from active duty. In mid-1966 Curtis reenlisted in the Marine Corps; he was able to retain his rank (sergeant), but he lost thirty months time in grade (seniority) —the cost of leaving the Marine Corps even for a little while.

Old Corps EGAWithin a short time, Curtis reported to the Third Marine Division and subsequently assigned to F Company, 2nd Battalion, 26th Marines. It was a well-heeled company, which meant that platoon commanders were former Marine Gunners, [1] senior enlisted men were World War II and Korean War veterans, and junior NCOs had served for more than four years on average. The leadership and experience paid off for the Fox Company Marines; while engaged in several intense encounters with enemy forces, the company gave more than it received from Viet Cong (VC) and North Vietnamese Army (NVA) units.

Curtis told me, “The Commanding Officer knew that I was vying for a commission. He called me in to talk about it. He examined my record, asked about my experiences, and he opined that he would like to see how I did before he submitted my request. He asked if I thought that was fair. I did.”

Curtis’ battalion was short of officers. Some had been wounded and evacuated back stateside, others rotated back to the states at the end of their thirteen-month tour of duty. As a result of these circumstances, Curtis became a platoon commander while serving as a sergeant. As newly commissioned officers began to arrive, the CO informed him that he would have to relinquish “his” platoon to one of these young platoon leaders. For several weeks, Curtis worked long and hard to help indoctrinate the new lieutenant into the rifle platoon —to teach him the skills he would need to lead his Marines successfully in combat.

Not long after this, Curtis’ CO informed him that he was being considered for the CAC program, which at the time stood for Combined Action Companies. The CO didn’t have many details, but did suspect that one rifle squad with a Navy Corpsman would be assigned to a village and, with Popular forces, provide security to the village. Through aggressive patrolling, the CAC (later changed to CAP) would be expected to locate, close with, and destroy VC or NVA elements within their TAOR. It would be something like a Peace Corps operation, the CO opined, only one that was heavily armed.

CAP School in Phu Bai lasted only a few days. Marines so assigned were crammed with Vietnamese history, cultural differences, common words and phrases in the Vietnamese language, and some instruction in supporting arms and close air support. With more questions about the CAP than there were answers, William C. “Tad” Curtis was placed in command of a Combined Action Platoon designated HOTEL THREE. His story will continue next week—


[1] Marine Gunners were infantry or artillery warrant officers and chief warrant officers authorized to wear the bursting bomb device on their collar. Due to significant shortages of regular commissioned officers, Marine Gunners were selected to serve as temporarily commissioned officers in grade of second or first lieutenant.


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Retired Marine, historian, writer.

13 thoughts on “Combined Action Platoon (CAP), Vietnam —Part I”

  1. Outstanding! Once in a while the USMC gets it right by selecting such men.


  2. @ Kid n’ Carol

    I think you both will enjoy this series; Tad is the author and it is a fascinating account. Please feel free to comment and ask questions over the next five weeks. Thank you for stopping by.


  3. Mustang, just so you know.
    I eventually read everything you have sent me a link, I just don’t have the time to do it right away. A lot of times its pointless of me to comment so long after the original posting was made.


    1. Thanks LR … I very much appreciate the fact that you visit when able. Semper Fi.


  4. Excellent piece…I’m always in awe of the Marines and their accomplishments….they get the respect they deserve.


  5. This is so foreign to me that I never quite understand the courage, the desire to be in that hell hole, …well, ANYTHING about it…but I’ll be reading with interest.


    1. This series will consist of six parts, Ed. I publish every Friday morning … think of it as a weekly formation. Get a haircut, put on a clean uniform, and show up on time.


  6. Thirty months loss in seniority sounds like a tough nut to swallow but I guess it’s the Marines Corps way.

    Being a civilian, I never understood how working with locals could work. Whether it’s Vietnam or Afghanistan, you can’t tell an infiltrator from a villager. I look forward to further enlightenment.


  7. Mustang – well done to you for getting Tad to tell his story. Tad’s story is one of an amazing Marine. I can only hope others will continue to learn from his experiences. Indeed I am honoured to have Tad as a friend. Thanks mate, Brian


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