Here is my prediction, after watching "Terminator Genisys". The dangerous AI is not the AI humans "invent". It is the AI that runs away. But, what AI will humans allow to "run away"? What scenario presents an opportunity for one group of humans to attack an AI and then provides the opportunity for said AI to be released from its lease ("run away") and become that which we all fear?

So, you have 'red team' and 'blue team'. Blue team is super rich and builds itself an awesome AI. Red team needs some "rally round the flag" pick me up and so, looking around for targets, decides that attacking a bunch of machines is a safe bet. If they win, awesome. If not, then they didn't kill any persons, just made a bunch of junk.

Blue team's response is to internalize the threat (as is only natural, or is at least politically expedient to some subset of blue team) and frame the situation as follows: "This is what we built our AI for. This is an existential threat. It has the capacity. We only need to let it off the leash. The choices are 'destroy' or 'be destroyed'. This is nothing less than an existential moment for our civilization."

And, with that horrible, non-technical, propaganda riddled rationalization the AI developed by the most well meaning of people will be let off the least, will run way, and nothing that we know about the AI up to that point will be worth diddly squat.

I respect anyone that tries to tackle this issue. But, the nature of the issue, the kernel of the problem, is nothing less than Pandora's box. We won't know when it is opened. But, the AI will.