Dragon and Soldier by Timothy Zahn

(I didn't realize until after I finished reading that I can totally use this as a Men In Uniform book, because he is totally in uniform, albeit a mercenary one, for most of the book. I am going to bend the rules for all of my challenges as much as possible, if that wasn't clear.)

I really enjoyed the first book, Dragon and Thief, in Timothy Zahn's YA sci-fi series, "Dragonback." An orphan teen, Jack, who has been raised as a petty criminal, teams up with Draycos, a symbiotic alien, and the two of them try to save Draycos' people from another alien race bent on genocide. The first book chronicles how they meet, learn to work together, face off with some villains, and clash ideologically.
In the second book, Jack and Draycos are trying to track down the people who are helping the villain-aliens, and to do this they decide to infiltrate a mercenary group. Draycos is increasingly uncomfortable with Jack's ambiguous moral center and selfish attitude. Draycos takes it on himself to train Jack as a warrior, both mentally and physically. His task is NOT helped by the mercenaries, who are kind of the worst example of a militarized body ever, and the fact that Jack really, REALLY does not like guns.

Reading this book directly after Starship Troopers was a little bit painful, because of how incompetent all of the military figures are in this book, except for Draycos (because Draycos is awesome). But Zahn generally has awesome military characters, so he makes sure that all his characters make fun/criticize the ineptitude exhibited by the mercs here.
I think a big strength of this series is how different Jack and Draycos really are. Draycos thinks about others first, he is very skilled in fighting, stealth, and such, he's a bit of an intellectual, and he has a very strong moral code. Jack is very clever, good at getting in and out of tricky situations, and of course knows all about stealing, breaking into places, hacking, and manipulating people. He usually ends up doing the right thing, but it's a struggle for him. This dichotomy between them, of course, is nicely echoed by the fact that Draycos literally can't live without Jack (or a similar biological pile of life-force, lol).
I think a weakness in this series is that Timothy Zahn is very careful about his content-level. He usually writes for adults (and his adult-novels are very clean, generally) so I think he's not quite in tune with just how much dark violence teenagers can take. At several points in these books I'm expecting something much darker than what it will actually happen, so then it's like, oh, okay, everything's fine, everything's chill. But maybe the stakes will heighten in future books?

Specifically in this one, I loved the rivalry between Uncle Virge (the AI computer on their ship) and Draycos, especially the warrior-poetry sub-sub-plot (is that a term? It SHOULD be!).

We are also introduced to a new character, Alison, who is a teen girl with Secrets and may or may not be a love interest for Jack. I think I would have cared more about her if she wasn't quite so soulless, and also if she had a little more common-sense. But I have hopes for her in future books. She's a bit like a young, learning-curve Mara Jade (for TZ fans).
Overall, not the best Timothy Zahn book I've read, but it's a good setup for the rest of the series, I think, and I am eager to have time to read the rest (which are sitting on my shelf, all pretty and clever). I gave this 4/5 stars for enjoyability.