What’s the difference? In reality, less than one might think. In general, I think, the “Action Adventure” genre, as exemplified (and coined) by Don Pendleton’s Executioner series, which spawned multiple spinoffs and inspired others (there is actually a flashback in SOBs #3, Butchers of Eden, in which Col. Barrabas remembers a night fighting back to back in Vietnam with Sgt. Mack Bolan), has generally been looked down upon as cheap, poorly-done “pulp,” with even less merit than comic books. “Techno-thrillers,” ostensibly started by Tom Clancy with The Hunt for Red October, are considered better quality and more realistic, though still sneered at by the literati (I had a high-school English teacher speak dismissively of Clancy as “pop-lit.”).