It's going to happen and soon. I'm only hoping that computers will never be self-aware.
Self-awareness is the capacity for introspection and the ability to recognize oneself as an individual separate from the environment and other individuals. While consciousness is being aware of one’s environment and body and lifestyle, self-awareness is the recognition of that awareness. (my highlight)
If computers and artificial intelligence never become aware of their awareness then maybe they would have no self-motivation (Motivated to achieve something due to one's own interest) to dominate humans. Disaster could still happen but it would be due to a mistake in programming.
But if computers and artificial intelligence become self-aware beings then we could be in even more danger.
There's an excellent lecture with interesting ideas on this topic. It's about 16 minutes long.
Here's the link:
Nick Bostrom- What happens when our computers get smarter than we are-