The events in Terminator would be impossible to happen. Because
The technology only became possible after they got hold of the parts from the terminator. But in order for them to get the parts from the terminator, the terminator had to be invented. But it could not be invented because the scientist who "invented" (stole) the technology for the terminator only did so because he was able to copy the technology from the destroyed terminator. The terminator would of had to be invented before the technology existed.
f*** me dead, you're a genius.
I have been living a lie.