The first exemple you give, Terminator, is exactly that. In the original story (T1 and T2, before they started rebooting the story again and again) Skynet doesn

The first exemple you give, Terminator, is exactly that. In the original story (T1 and T2, before they started rebooting the story again and again) Skynet doesn't fire on the US. It fires on Russia "because it knew the Russian would overwhelmingly retaliate and kill its enemies in the US". The idea was that Skynet could not kill all us forces, no where close, but retaliating Russian could (given the strikes against them had let most of their forces and weapons standing, and the US didn't have access to its own to stop them), and Skynet could trigger MAD.