Moutain Meadows Massacre

This is a movie of a FAIR presentation by Richard Turley a Church Historian, presenting his study into Mountain Meadows Massacre.  He talks about how such a thing could happen.  He draws on study of mass killings, and what conditions lead to mass killings.  The only problem is the video cuts off before he is done, and it is clear he was going to say more. 
http://www.youtube.com/watch?v=tok62ytBrDo
There is an accompanying article by FAIR which talks about Mountain Meadows, and responds to those who try to say that it was the work of Brigham Young.  James Haslam was the brother charged with carrying a message to Brigham Young, to ask what they should do with the emigrants.  Brigham Young's response was to provide them safe passage.  Unfortunately he did not return to Southern Utah in time to prevent the massacre, it had already taken place.  Also, when Brigham Young was first told what happened, he was told that no White people participated in the massacre.  This was not the case.  In fact it was white planning, and white inciting and white carrying out the plan. 
Although looking back, I find it difficult to see how the local leaders could let this happen, although I was not there during the time, nor did I live through years of persecution, nor was I threatened with an army coming to do who knows what.  At the time of this event, all anyone knew was that the army intended to wipe out the Mormons. 
Looking at this article is very enlightening.
http://en.fairmormon.org/Mountain_Meadows_Massacre/Summary