Illusion Of Explanatory Depth
People hold passionate views about topic that they don't really understand. They think they understand it - but its only apparent when they are asked to explain it in detail. That is where they will fail.
One approach to getting people to loosen their views about something is to NOT ask why they believe it - but rather how they'll implement their ideas. Or How it will translate on-ground. This will show them their own lack of understand of the nuances of the idea.