Diplomatic Security Meets Geopolitical Chess: A Novel
BOOK REVIEW: SENTINEL
By Mark Greaney/ Berkley
Reviewed by: Neal A. Pollard
The Reviewer — Neal A. Pollard is an adjunct professor at Columbia University and was the lead cybersecurity executive for a global Swiss bank. Prior to joining the cybersecurity industry in 2011, he spent 18 years in the US counterterrorism community, as a defense contractor and an intelligence officer. In 1996, he co-founded a counterterrorism corporation, sold in 2006 to Blackwater’s holding company. He is working on his first novel, “Ordinary Spies” a spy thriller focused on the nexus of nuclear smuggling and Central Asian cuisine.
REVIEW — Sentinel is the latest thriller from Mark Greaney. Greaney is best known for the Gray Man series of novels. He also was Tom Clancy’s collaborator on the last three novels before Clancy’s death in 2013, when Greaney continued the Jack Ryan character for four more novels. Sentinel is stand-alone, separate from the Gray Man or Jack Ryan novels.
Sentinel’s hero is Josh “Duff” Duffy, a Diplomatic Security specialist assigned to the Regional Security Office of US Embassy Accra, Ghana. His wife Nikki, a US Foreign Service Officer, is also stationed in Accra, and they’ve brought their children over for a vacation to the relatively safe country. Duff’s background is military: four years Army, followed by a stint as a private military contractor for United Defense Services Group (UDSG), serving in garden spots like Afghanistan and Beirut, where he lost a leg to combat. Duff has heroically overcome his physical disability with a prosthetic leg, but he’s still plagued by PTSD nightmares. Greaney does an excellent job with Duff’s character, showing the daily struggle heroes endure just to normalize physical and mental challenges.
The novel is set in present-day Ghana, a stable, pro-West country in western Africa. The novel describes China’s aggressive pursuit of African natural resources, using means such as “debt-trap diplomacy” of predatory lending to gain outright control of infrastructure and resources. Beijing sees control over Ghana’s democratic government as the key to controlling most of Africa. So, it sends an intelligence officer from their Ministry of State Security (MSS, the Chinese rough equivalent of CIA), named Kang Shikun, to orchestrate a coup, install a military president friendly to China, and embarrass the United States. Kang launches his plot using Sentinel, a private military corporation consisting mostly of Russians. Sentinel’s role is to arm and poorly train rebels to attack the capital, while also seizing a massive dam on the River Volta, to cut the electricity the dam provides the country. At the same time, Kang manipulates other insurgent factions in a complex scheme, with paramilitary support from Sentinel and cyber and disinformation support from an MSS team on the ground.
The action begins with the United States and European Union making a joint investment in Ghana, with a series of publicity stops by their ambassadors at photo ops around the country’s infrastructure projects. As part of security, Duffy accompanies the US Ambassador and his diplomat wife on these stops, making an unscheduled stop at the aforementioned dam, at the same time the rebels and Sentinel are seizing control of it. The Sentinel commander is Conrad Tremaine, call sign “Condor,” a ruthless South African mercenary, and former colleague of Duff’s at UDSG. A firefight ensues, and Duff recognizes his old colleague Condor, clearly no love lost between them. During the firefight Duff also obtains evidence tying the coup to Sentinel, and thus eventually the Chinese. As the coup rages, Condor’s men take Duff’s children hostage, forcing a showdown between Duff and his old, hated colleague.
Greaney is known for realism and detail in his description of combat, and he certainly continues that flair here. His combat scenes run long and go into the kind of technothriller detail you’d expect from the Clancy genre: if this is your thing, he delivers. He also gives an excellent glimpse into the workings of US Embassy security, especially those in the State Department, US Marine Corps, CIA, and local Foreign Service Nationals, all working to advance the country’s interests while protecting the civilian front line wherever US diplomats are posted abroad. Take a visit to a US Embassy in Africa, Central Asia, Near East, or the Caucasus, and you might be appalled at just how few people are protecting so much work that gets done there.
Greaney uses a familiar and important context for his novel: nations playing Great Power games to pursue natural resources (gold and diamonds, in this story.) Greaney also hits on a theme I believe merits attention – private military companies (PMCs) as state proxies. Sentinel is a fictional remnant of the real Wagner Group, the notorious Kremlin-backed paramilitary group that was central to many of Moscow’s paramilitary operations in Africa, Syria, and Ukraine, where it emerged more overt with 50,000 combatants. After the 2023 suspicious death of Wagner’s leader Yevgeny Prigozhin, Wagner dispersed, but didn’t die. In February 2024, BBC reported that Moscow offers African governments a “regime survival package” in exchange for access to natural resources. That “survival” is assured by personnel and materiel from Wagner’s old “Africa Corps,” now under Moscow’s direct control.
Greaney uses personnel from this same Africa Corps as the formation of Sentinel, telling a compelling story of the real role PMCs will continue to play in geopolitics. Wagner was far from the first – mercenaries have a long history in great power conflicts. The origin of the British East India Company was, at heart, a pursuit of resources abroad. Governments will continue to rely on private contractors, not just to bear arms but to transport them, too. From the old Swiss Oerlikon-Bührle to the modern Global Ordnance, even NATO has difficulty arming friends and allies in conflict zones, without the help of corporations.
Tactically, Greaney is solid in his narrative, raising only a couple questions for me, especially the brazen nature of China’s covert action, and Kang working under non-official cover as private security protecting Chinese commercial interests. Irrespective of cover, connecting Kang to Beijing wouldn’t be much of a leap, and I’d want diplomatic immunity. I don’t know what the Ghanian punishment sentence is for staging a coup, but it can’t be pleasant. Despite some small questions, Sentinel is a compelling read for fans of the genre, hitting on themes we’ll continue to read in the newspapers.
Sentinel earns an impressive 3.5 out of 4 trench coats
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