So T4 will probably take place after judgement day, maybe tell how the machine vs human story unfold, maybe T5 will tell how it ends kinda like matrix 3 or maybe T4 will be the end. Machines - All computers worldwide remaining after the nuclear strike are running skynet v1.0, AI software? - They have to begin from scratch? the movie showed early models of the hunter killers. For them to make more advance models and more terminators, they will have to make more factories and will take time. Humans - 3 billion deaths - Human civil wars? with almost all digital comm knocked out, the russians and chinese will think the US strike them and vice versa, there might be a war between humans before everyone realizes the machines are the real enemy, thus giving time for the machines to build up their forces Hinted at all 3 movies, it seems the humans are fighting gorrilla warfare against the machines, meaning they are largely outnumbered and much weaker?