I discovered the Saga graphic novel series this year, written by Brian K. Vaughan and illustrated by Fiona Staples. This graphic novel series has both science fiction and fantasy elements and explores the tragedy of war. Even the winners lose. This series is ongoing and I highly recommend it! Please heed the trigger warnings, though.
I also read Omar El Akkad’s American War. This book had a similar theme to Saga, but took place in a near future America where the South seceded again after refusing to stop using fossil fuels. Where Saga’s sorrowful plot twists are catapulted in magnitude by their extreme nature (e.g. victims of war swallowed up by space giants, for instance), American War hits closer to home with its plausibility.