This video clip is a study in the psycholgical power of a unified crowd over its oppressor. It begins with a cop pepper spraying a whole line of sitting students for no apparent reason except that they wouldn't comply. They are sitting peacefully, waiting to be arrested for non-compliance. As the video progresses and the crowd's chanting becomes more unified and louder, you begin to see fear and confusion in the eyes and body language of the cops (watch for it). You can feel the anger in the peoples voice(s) and the cops have no choice but to retreat.