History Literature / ExpeditionaryForce

** The issue for humanity basically comes down to "you don't even have the tools you need to make the tools you need to make this tech"; and maybe a few iterations beyond that. Skippy estimates that even if humanity was left completely alone to work on upgrading, it would take at least 300 years to get anywhere meaningful. As an example of how far tech requirements can go, the Maxolhx, admittedly one of the most advanced species in the galaxy, built a facility very close to a ''[[https://en.wikipedia.org/wiki/Neutron_star neutron star]]'' in order to create some of the exotic matter needed for their tech. And it still took them about 60-80 years to get it built, and work through issues before they got anything useful out of it.

* VichyEarth: Common strategy by conquering species, partly for the reason of adhering to TechnologyLevels, but mainly general distaste for interacting with lower species, is to install collaborative local puppet governments. Human leaders on both Earth and the alien planet Gethanu (known to humanity as Paradise) are effectively blackmailed into atrocious collaboration with their Kristang conquerors. The Thuranin did this to not to the Kristang government, but to the ''society itself'', turning a matriarchal society into an aggressive caste-based one ruled by the warrior caste.

The series has a spin off called ''Mavericks'' following troopers from the Paradise planet.

* VichyEarth: Common strategy by conquering species, partly for the reason of adhering to TechnologyLevels, but mainly general distaste for interacting with lower species, is to install collaborative local puppet governments. Human leaders on both Earth and the alien planet Gethanu (known to humanity as Paradise) are effectively blackmailed into atrocious collaboration with their Kristang conquerors.

* SuperiorSpecies: Apart from every species in the galaxy in general being superior to humanity in every way, there is also a hierarchical chain of superiority. At the top of the chain are the Rindhalu and the Maxolhx. The Maxolhx have the Thuranin and Bosphoraq as clients, and the Thuranin in turn have the Kristang as clients.
* TechnologyLevels: The combatants of the ForeverWar are generally restricted by an unspoken rule to only fighting other species at a roughly equivalent technology level. The Rindalhu and Maxolhx are at the top of the pyramid, with the Jeraptha, Thuranin, and Bosphuraq and the next level below, and the Ruhar, Kristang, and Wurgalan at a level below that. Humans and other pre-starfaring species are at the bottom of the ladder, and anything [[LostTechnology Elder-related]] is way at the top.

* StandardStarshipScuffle: (Deconstructed / Discussed / Conversed) FasterThanLightTravel notwithstanding, Space Combat Maneuvering is otherwise largely treated from a hard-scifi standpoint and described in great detail, with long ranges, stealth, orbital mechanics, acceleration effects, and light delays. It is indeed repeatedly discussed between characters that it "doesn't work like on TV" when an unrealistic "Hollywood-style" tactic is suggested.

** Ships can't form jump wormholes if they're too deep into a gravity well, with the viable minimum jump altitude depending on the ship's technology level.

* NoBiochemicalBarriers: While not every species is compatible with every biosphere and often has to bring its own food, every species is generally able to walk around in the open air of any habitable planet.

** The issue for humanity basically comes down to "you don't even have the tools you need to make the tools you need to make this tech"; and maybe a few iterations beyond that. Skippy estimates that even if humanity was left completely alone to work on upgrading, it would take at least 300 years to get anywhere meaningful. As an example of how far tech requirements can go, the Maxolhx, admittedly one of the most advanced species in the galaxy, built a facility very close to a [[https://en.wikipedia.org/wiki/Neutron_star ''neutron star'']] in order to create some of the exotic matter needed for their tech. And it still took them about 60-80 years to get it built, and work through issues before they got anything useful out of it.

* InsufficientlyAdvancedAlien: Humanity flies around the galaxy thanks to the magic of Skippy, but humans barely understand how to operate a starship, let alone build one of their own. [[spoiler: As of Book 10, UNEF Earth manage to fly The Dagger by themselves, although it's presumed that Skippy created a control system for the ship that Humans can use without issue]]

* {{Irony}}: Skippy thanks Bishop for teaching him the value of empathy [[spoiler: right before he abandons Bishop and the rest of the Merry Band of Pirates to their likely deaths from hostile alien forces. Thankfully he regrets this decision and comes back for his friends]]

* HumansNeedAliens: At first, humanity thinks of Kristang as its protector. When it becomes clear that the Kristang think of humans as disposable cannon fodder, humanity (or at least the portions of humanity that know of him) turn to Skippy for protection. Another example is UNEF-Paradise pledging allegiance to the Ruhar after the Kristang show their true colors.

*** [[spoiler: It works on Joe and Smythe at first, until Joe opts to make fun of the spider. He then proceeds to get angry enough that whatever fear remains is overridden by his anger at the Rindhalu]]

* HumansAreSpecial: (Zig Zagged) Humans are constantly reminded how weak, low-tech, unexceptional, and under-evolved they are, but regularly demonstrate a "low-tech monkey-brained" problem solving capacity able to overcome impossible odds and defeat higher technology levels.