Each to Each by Seanan McGuire
I read this story in "The Best American Science Fiction and Fantasy 2015" and originally published in Lightspeed Magazine.
You can read it online for free at : http://www.lightspeedmagazine.com/fiction/each-to-each/
This story had women, military, blood, and mermaids. How could you go wrong? A government who fills their subs up with nothing but women, turns them into sexy mermaids, fined tuned military machines, and then sends them under the water to explore.
This takes place in a future America where we’ve lessened our grip on space travel and exploration, but decided to explore and take over the underwater real estate and resources. Part of doing that is creating genetically, and physically, modified humans that can breathe, swim, survive, and fight underwater.
Women are funneled into the Navy. If they apply for the Army, or the Marines, they are quietly pushed in the Navy. Then put on all female submarines for duty.
This story sort of reminds me of the movie Water World with Kevin Costner. It’s not exactly like the movie, or the plot, but just reminded me of the movie with the whole mermaid, breathing under water stuff going on.
This story also deals with women in the military. The political arguments and debates about women in the military and combat. It is poking fun and hanging a lantern on what is wrong with current way of thinking.
Eventually the main character of this story is offered a chance at redemption. A utopia and relief from her current position in life.