Redliners

Redliners is a Military Science Fiction story by David Drake about a burnt-out elite unit sent to guard a group of involuntary colonists on a Death World.

The human civilisation is at war with the Kalendru (nicknamed Spooks), a race of aliens who understand the concepts of "master" and "slave" but not of "equals." Strike Force Company C41's veterans have all redlined, become too dangerous to re-integrate into civilian society, after a mission goes disastrously wrong. However, the bureaucrat in charge of the Unity wants to run an experiment to give the redlined strikers a chance to redeem themselves.

Can be found online for free here or downloaded in a variety of formats here.

The Setting Provides Examples of the Following Tropes:
 * Alien Geometries: The Spooks don't like constant-radius curves or right angles.
 * The Atoner: John Smith, a heroic example of the Well Intentioned Extremist, who feels regret for the merciless way in which he used his soldiers. Several of the strikers also qualify.
 * Bodyguarding a Badass: Early on, the major has a bodyguard whose sole purpose is to keep him from doing anything stupid like trying to lead an assault from the front; his job is to lead, not be a badass, though badass he is.
 * Chekhov's Gunman: We're told that
 * Death World: David Drake enjoys this trope. The entire ecosystem of BZ 459 is constantly evolving new ways to try and kill the civilians. Algae which blocks up the fans of their air cars. Trees which spray those who come too close with fast-hardening strongly acidic sap, plants which shoot spikes if people come close or if it gets shot, vines which act like grappling tentacles, streams of water with an under-layer of concentrated sulphuric acid at the bottom ... you get the idea.
 * The strikers note that the original surveyors of BZ 459 nicknamed it Hell. They later think back to how pleasant the planet seemed at the time it was surveyed.
 * Everything Trying to Kill You: Literally. Streams hide an under-layer of concentrated sulphuric acid. Genetically engineered natives who mindlessly attack the settlers. And lets not even get started on the flora.
 * And these defences tailor themselves to the intruder. Blohm notes that the spikes are poisonous to the Kalendru who were there before them.
 * Everyone Calls Him God: Project Manager Jafar al-Ibrahimi, because he has life-and-death authority over all the civilians and strikers on the expedition..
 * Infant Immortality: Averted. The Kalendru have extremely fast reactions, so the strikers have learned to never hesitate. Caius Blohm, the point man for C41, hoses down a room of Spook women and children before he realizes his mistake. It affects him.
 * Kinetic Weapons Are Just Better: The strikers use stingers, electromagnetic pellet rifles, as their primary weapons, while the Spooks use laser beams. The stingers are massively damaging at the close range that Strike Force missions take place at.
 * It's noted, however, that striker rockets and stingers are totally ineffective against Kalendru tanks. Their Heavy Weapons unit uses plasma cannons and larger rockets.
 * Mind Probe: The standard method of interrogating Kalendru prisoners.
 * No One Gets Left Behind: The strikers, especially Major Art Farrell, live and breathe this trope.
 * Scarily Competent Tracker: Caius Blohm, the striker's best scout. He becomes attuned to the jungle in such a way that his commanding officer admits that he is the group's best chance of success.
 * Soldiers At the Rear: An event used to demonstrate that the strikers are all a little bit over the edge has them overreact to a REMF telling them they're not allowed in the bar in their BD Us. They get their drinks while destroying the bar.
 * The Stoic: All Category Fours. Also Caius Blohm.
 * The Stoic: All Category Fours. Also Caius Blohm.