A few years ago I decided to begin producing a serial, including eventually posts to Facebook Notes and to my timeline regarding a partly machine encephalovirus, and what life would be like to exist with one. There is no level of insanity involved in my posts. It's a useful exercise, and it gets my creative juices flowing. Being a programmer can be a stressful life, and it helps to do different stuff.
What we really have to worry about when it comes to machine weapons systems are the ones that we can't see, weapons systems that can infect us like a virus. Particularly troubling would be an encephalovirus, a virus that infects our nervous system and eventually acquires the ability to change our behavior and our thought processes. The idea of nanotech has been explored in depth in science fiction, but most of the writers refer to nanotech as if it's some kind of utopia for humanity. My take is that it could be partly utopian and partly dystopian.
It would be possible for nanotech to become weaponized, and to even take over all human life, possibly without us knowing it. The wrinkle or twist in my writing is that I entertain the possibility of an alien race that may no longer exist that produced and possibly weaponized nanotech. This nanotech floated to Earth some time over the past few million years of mammal evolution, far before we had any technlogy more modern than the campfire, and it infected us, giving it plenty of time to become as stealth as possible.
Knowing that the modern human as it exists today is a machine hybrid is the topic that I explore. As human nanotech advances, once we detect our infection how do we go about getting rid of it, and what does it do to defend itself? Does it mean our destruction, can we learn to live in peace with it, or some other possibility?
Substitute an alien race for humanity a few generations from now, and you have roughly the same story, but I wanted to work with something that could be possible today without using with a presumed future human society. Roughly the same concerns as the general would apply.