The thing is i think they tried total war, at least for a couple of years, it just isn't how things work anymore with modern warfare, i mean partisans were already present during ww2, if you mean total mobilization the stoppage of treats and non essential goods will crash the market hard enough to dry the US coffers before any battle, so I don't think the US is physically capable of even fighting total war at the moment. Of course a proper fascist would just suspend the markets and roll the dice so it is not entirely impossible either. Anyways, as I said offensive warfare is basically unwinnable, Turkey, Ukraine, Saudi Arabia have all tried unsucessfully with significant enough means that I don't think they would be qualitatively different from conflict with an official state actor, i think the premium we have given to infantry numbers are extremely severely reduced with new techniques, technologies and indigenous advanced fabrication (you can't say the amount of troops deployed in Yemen for instance 100000-200000 for each side would be significantly different from total war)