Read this article and then think how you, with what you have between your ears and in your pockets, purses, and vehicles, would handle being in this situation. In the traffic jam, trying to get out of the fairgrounds on foot, trying to get out of the crowd, trying to get around the melee; run all of the scenarios.
Many people paid a high price in my home state a few nights ago; let's try to learn something from it so their suffering isn't entirely in vain. I cannot imagine that this is the last time something like this will happen in the foreseeable future:
edit This is a better description of the actual event: