John Stratton is a soldier in the British SBS.
The Special Boat Service is the Special Forces division of the British Royal Navy. Comparable to the SAS of the British Army, this highly skilled group of largely Royal Marines performs duties much as the American Seals, being the elite fighting force trained to handle the nastiest of black-ops; infiltrations, rescue, demolitions, or reconnaisance as needed.
Stratton is one of their finest, a Marine who has served in the SBS for a good number of years at the start of the series and has no thought of quitting. He could easily be a poster board for the Service with his rugged good looks, tall, strong, athletic build, and a sternness of expression that would make most intelligent people take pause before starting anything. His taciturn nature and piercing grey eyes, however, would certainly dissuade anyone from asking him to do it.
Very little is given about Stratton's origins, what made him the fighting man that he currently is or prompted him to join the Service. He is single, having never tried marriage. He seems without a steady companion. Though many have offered, he knows with his job and the crazy schedule he keeps, it would not work out too well.
Stratton is tremendously loyal to his comrades and has risked his own life on several occasions to save theirs. These people in turn would fight for him but he would be reluctant to ask. Towards his superiors, his attitude is quite a bit different. Respectful and slow to anger, he nevertheless has little use for the higher-ups who have never faced what he and his colleagues do. And he is independent enough to do things his own way and suffer the consequences later when he knows he is right.
The books about Stratton are included because in addition to his SBS duties, he is on constant call by MI-6 for clandestine work in remote areas of the world and will, during the course of the series, even work on occasion with the CIA.