I wouldn't say it's an "autistic" level of obsession, but effective cases of guerrilla warfare have always fascinated me. Fighting forces like the Vietcong, the Iraqi insurgents of the mid-2000s, and the various rebel organizations of specifically West and Central Africa are some examples.
I don't get autistically obsessed with military shit because the military is just a death cult. I find the idea of some military tech to be funny/interesting though like emotional regulation chips, flechettes and vision augmentations.