There was a war that nobody talks about.
Why doesn’t anyone ever talk about The War, or the Before Time? Lots of dystopian novels lead us to believe that Bad Things Happened, which is why things Are the Way They Are, but they never go into any detail. Maybe I’m alone in this, but I want detail! I want to know when the war happened, why, and how many intrepid, good-hearted characters died so I can be sad about them.
The Hunger Games does this, Divergent does this, Do Androids Dream of Electric Sheep? does this (tell me more about World War Terminus!), The Giver does this (understandably, but still). The Handmaid’s Tale subverts the trope, but when it comes to dystopian lit, more often than not, I find myself left wondering.