Skynet obviously knows the human resistance is going to send someone back in time; why even entertain the option? Why not wire the machine to just explode after the T-101 goes back? Then no one goes back to help anyone, and Sarah Connor is dead. We’re five movies into this franchise now, and every single damn instance where something goes back in time, something else follows it. This is really predictable. Someone needs to close the window so the flies stop getting in. Even Skynet should be able to figure that one out.