In addition to his own work, Pournelle also was half of what was, in my mind, one of the best collaborative pairings in science fiction. Pournelle, alone, had studied aerospace engineering, sociology, and other subjects, with an ability to understand the impact of technology from his own and other disciplines that few had. His take on the future was full of hope and adventure, swords and impossible quests, but also gritty. The militaries acted like functioning organizations. The technology felt lived in. The consequences of his tramline based FTL system in the CoDominium books, and the stories like King David's Spaceship that followed, followed rules as merciless and consistent as any "hard" science fiction work. He had a feel for history that breathed life into his stories, even when not explicitly informed by true events.
The other half was Niven - with an eye toward the utterly fantastic. Niven could get in someone's head. His stories featured aliens that were truly alien, their very thoughts and assumptions driven by their instincts and biologies. Looking at his stories, he lived and breathed the big ideas of stellar constructs, and what if. His Ringworld inspired, among other things, the setting for Halo.
The two together? Amazing.
In my opinion, and despite the high esteem in which I hold Dune, Their work on The Mote in Gods Eye is easily not only the best first contact novel ever written, but the best science fiction book written short of Gene Wolfe's long and new sun books, while being far more accessible. There is a scene near the end, the result of events that could only have come from both authors working together, that is the stuff of utter nightmares, and yet, only involves one space suit, and its contents.
So - all these words, and I've yet to mention, among their other works, Oath of Fealty.
When Pournelle stopped There Will Be War at the ninth volume, he started a new project, published by Baen, called Imperial Stars. It explored governments of the future, more than straight warfare. Included in the essays was an old Campbell essay where it was discussed tribesmen, barbarians, and civilized people, and that to a barbarian, civilized people looked an awful lot like weird tribesmen, subsuming themselves to the tribe. he closed with the point that future political changes past "civilized" may take on structures that look a lot like the old, to our current selves.
To me, Oath of Fealty is borne of that essay. It centers on a large arcology - think of it as a massive building which is a self-contained city - the first one to be successful, built near LA, called Todos Santos. From Infogalactic:
In the near future, a race riot results in the destruction of an area just outside Los Angeles. The city sells the construction rights to a private company, which then constructs an arcology, named Todos Santos. The higher standard of living enjoyed by Todos Santos residents causes resentment among Angelenos. The arcology dwellers have evolved a different culture, sacrificing privacy - there are cameras (not routinely monitored) even in the private apartments - in exchange for security. The residents are fiercely loyal to the arcology and its management, and the loyalty runs both ways. During the course of the novel, Todos Santos is compared to a feudal society, with loyalty and obligations running both ways, hence the title.
Pro or con, it explores issues of modern crime, of security, of the surveillance state, of loyalty, of the fragility of large and complex systems, ecoterrorism, and of the debts and obligations of feudalism. It also features one of the earliest examples of computer interface implants, beating out the more fantastic version that would show up in the works of William Gibson by a couple years.
Also, near the very beginning, is a scene that still makes me laugh in a dark way. Due to the popularity of the tall building for wannabe jumpers, the management made it very difficult to get to the roof. Since they couldn't stop everyone though, there was one, final, psychological mindfuck. As the prospective jumper finally approaches the edge, he is greeted by a diving platform. Scrawled on the wall near this by some anonymous resident, is the graffiti "Think of it as evolution in action."
That phrase describes both the societal changes in Todos Santos, as well as the individual jumper taking himself out of the reproductive pool. Most who made it that far are... dissuaded, realizing that not only did the universe not care about their grand gesture, but were willing to give them a few extra feet of height for the sendoff, and mock them.
The story fits well into the tone of Pournelle's short stories in High Justice, of individuals and companies doing what they can to stand up against tyrants, and worse, bureaucracies that take over every aspect of life. It's a fun, but thoughtful read.