The hastily assembled Black Lives Matter protest held in downtown Dallas yesterday was a textbook example of how a protest should be handled. It was peaceful, focused, well-organized and the Dallas Police Department, widely considered one of the more progressive in the country, were supportive and non-threatening. In total about 1000 protesters and about 100 police officers were gathered together, and just as the event was ending gunmen began to open fire on the crowd. When the Dallas Police were unable to subdue the suspect, and the officers felt that continuing the firefight would only put more of their officers at risk, they made a decision to send a bomb disposal robot into the garage and detonate a charge near the gunman, killing him. According to experts, this was the very first domestic use of an unmanned robot to kill an American citizen. You can read more at 3DPrint.com: https://3dprint.com/141627/dallas-shooting-robot-bomb/