How deep does loyalty run between father and son on opposite sides of apocalyptic, civil war?

As winter blocks the mountain passes during the Black Autumn apocalypse, the conquering forces of the Mexican drug cartel occupy and enslave the population of Flagstaff, Arizona. Ex-mercenary, Green Beret, Bill McCallister plays the shrewd kingmaker while his adopted son, Noah Miller, fights and bleeds for the American partisans, opposite his own father.

The ties between father and son strain to the breaking point as ever more powerful weapons find their way onto the desert battlefields of armageddon: Abrams tanks, A-10 Warthog jets, and finally a tactical nuclear warhead.

When convictions collide, can the love of a father and a son withstand the maelstrom of war?