Bombing of United Flight 629 over Longmont in 1955--a man put a bomb in his mother's luggage and 39 people were killed. This was the second ever bombing of an airplane over the U.S.
http://en.wikipedia.org/wiki/United_Airlines_Flight_629
Don't forget John Hinkley.
The Granby bulldozer in which Marvin Heemeyer had a beef with the city council so he put armour on his bulldozer and destroyed the town. (Luckily there were no deaths other than Marvin who killed himself.)
http://en.wikipedia.org/wiki/Marvin_Heemeyer
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So why do these happen? Could it be the same reason that there are more suicides in the less-populated western states. There just isn't the social structure to keep people well grounded. The convergence-of-time-and-place argument could also play a role. At this time in Colorado's history, we are having growing pains. Again, the lack of social stability plays a role in this. People see buildings going up where there was once open spaces (The Granby guy had a touch of this problem). Obviously, the pressures that our young people are facing is a major problem. The Columbine killers, the Aurora shooter and the Deer Creek Middle school shooting all were cases where the shooters were being treated for mental problems.
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