Here are my analyses:

When somebody hacks into one's computer, he can't do any physical harm, he sure can steal money, spy on the victim, but he can't make the computer burn or somehow harm the victim.

The computers that can be used for doing real damage (i.e. bomb activation, drone command and control centre, etc.) are well protected from the hackers (not connected to the internet and physicall inaccessable).

Controrary to this, the self-driving cars are potentially dangerous and will be widely accessable and hackable, I see this as a real problem. We should not allow a computer to do things that can kill people, and a computer-driven car can kill people.