Affirming a world view
It really never ceases to amaze me that there are people who think that their world view is right, and unquestionably so, giving no quarter to rational or reasonable debate.
If one had suggested in 2005 that a single natural event could shut down airspace in most of Europe for about a week you would have been looked at strangely.
In 2010 we now know a single volcano in Iceland can stop planes leaving Lanzarote, and a lot of other places as well. People now are aware, at least in the back of their minds that this could happen.
Lets extrapolate this a little, five suitable volcanoes with the correct prevailing winds and almost all air transport could stop on the planet.
Welcome to a potentially disconnected world!
The other thing to take away from this notion is that we are not in control of our destiny, we can strive as best we can, after that it is in the lap of mother nature.