Apparently you and others have some sort of estimate of probability distribution over time leading you to being alarmed enough to demand action. Maybe it's say "1% chance in the next 20 years of hard takeoff" or something like that. Say what it is and how you got to it from "conceivability" or "non-impossibility". If there is a reasoned link that can be analyzed producing such a result, it is no longer a leap of faith; it can be reasoned about rationally and discussed in more detail. Don't get hung up on the number exactly, use a qualitative measure if you like, but the point is how you got there.

I am not attempting to ridicule hard takeoff or Friendly AI, just giving my opinion about the thesis question of this post: "what can we do to efficiently change the opinion of millions of people..."