The Iraq war
The Vietnam war
The anthrax hysteria after 9-11
The SARs epidemic that wasn't.
The Swine flu epidemic that was or wasn't depending on who is reporting
The 2008-2009 financial meltdown where we "had to destroy capitalism in order to save it"
Society needs experts, but the experts need to be held accountable and responsible for what they say. We don't get much of that, do we?