I would suggest that we limit our discussion to scenarios, leaving out the cause of the scenarios. If you're concerned about a Peak oil crisis, discuss how to prepare for a long-term gasoline shortage. That can be caused by Peak oil, a terrorist attack, a hurricane, an earthquake, etc. Then, hopefully, no one will argue about Peak oil or terrorists.
If your favorite psychic has predicted a horrible earthquake in July, don't say that. Just ask how to prepare for earthquakes. Then, hopefully, no one will argue about psychics.
Some scenarios will be specific in cause, of course, but there's no perfect solution.
What I hope doesn't happen is that the forum turn into a place where people post links to fear-mongering news stories about how the world is going to end (not talking about you specifically) . There's enough of that in other forums. Let's keep it simple.