I don't read too many zombie novels, none prior to John Ringo's effort, but I doubt if they usually open up with a bit of a discourse on Sartrean existentialism. Ringo's third effort in the zombie genre opens with a Marine being "counseled" over her depression from leaving her gunnery sergeant behind.
The book starts off with an incident at Guantanamo Bay, which has been under attack by zombies. It then shifts back to Wolf Squadron and the flotilla. Eventually they are assigned the mission of clearing Guantanamo. Much of the action involves the problems of integrating the regular Marines from the Guantanamo base into the ad hoc units formed under Wolf Squadron. After the naval base at Guantanamo is cleared Wolf Squadron moves onto a number of other islands.
There is a bit of satire on Survivor and other reality shows. One group of survivors includes a girl who is obviously modeled on one of the denizens of The Jersey Shore. Fortunately, from the reader's perspective, she doesn't survive long, and is barely mentioned except for obvious satiric reasons.
Ringo doesn't engage in lengthy discussions of politics and philosophy, but it is obvious that now that he has a coherent force gathered together the force will begin the long process of clearing continental land masses.
Next up, Boswell's London Journal, possibly followed by Dickens' Sketches by Boz, and an anthology of World War I poetry. All of which I'll be reading while travelling the UK.