Irish Defence Forces Leader Discusses Counterinsurgency at U.S. Naval War College

Col. Gareth Prendergast, Ph.D., of the Irish Defence Forces delivered a talk on counterinsurgency at the U.S. Naval War College in Newport, Rhode Island, on Oct. 29, 2025. 

Prendergast, who studied the U.S. Army Field Manuel 3-24 at the Army Command Staff College in Fort Leavenworth in Kansas, has released a new book, titled “Clear-Hold-Build: How the Free State won the Irish Civil War.”  

In it, he uses American counterinsurgency doctrine to analyze campaigns carried out during the war, which took place from 1922-23. He determined that local conditions played a significant factor in whether the “clear-hold-build” approach – championed today in American doctrine – was successful during that conflict. 

The three-phase approach calls for clearing an area – capturing, destroying or driving out the insurgent force – followed by holding the area by establishing a permanent friendly presence and then building support for friendly forces and their government by improving safety, as well as economic, social and medical conditions. 

Prendergast, a veteran with more than 30 years of service in the Defence Forces, has seven operational tours of duty overseas, including tours in the Middle East, Balkans and Mali. He currently serves as head of strategic design for the Irish Defence Forces. 

Prendergast’s visit to the school comes less than a month after a talk by Rear Adm. Oliver Berdal, Chief of the Royal Norwegian Navy, about the Arctic and emerging military technologies, and a week following a guest lecture in the Strategy and War course by former U.S. Secretary of the Navy John Lehman. 

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