Human beings mass-produced in the likeness of another. Ideally, the "duplicates" are spawned fully grown and endowed with formative memories. The clones are preferably female. They are selfless, loyal and obedient. They are cheap and easy to make, hence, plentiful and expendable. They are the slaves and cannon-fodder of villainy.
Ideas are not what make art and fiction inspiring. Notions are not what make them interesting. The insightful expression of a fancy is what makes art and fiction artistic. I am fascinated by the idea of people being mass-produced to serve a nefarious elite. I know the notion is appealing to the traditional yearnings of tyranny and oligarchy. Women are the natural victims of our species so who better to represent an exploited class?
War is a clash of hearts, minds, souls and strengths. It is people against people. Whatever the supposed reasons, war began as evil against good. Justice turned it into a struggle of good against evil. Yes, the petty squabble amongst themselves in the feuds of tribes and nations. The real war, however, has only ever been the one struggle.
The minions of villainy are seldom villainous themselves. They are simply the aimless, anonymous masses mustered to serve an agenda beyond their ken. The fictional theme of "mass-produced clones" is simply a colorful way of articulating this very real and common dynamic.