The black majority but politically powerless community in Ferguson consists of Americans who are constantly harassed and abused by police. The black community responded predictably to the exoneration of the white policeman. The results were riots, looting, and the destruction of property.
This response hardened the whites in their view that black people are criminally inclined and a threat to the safety of the lives and properties of whites.
The issue has been cast as white-black racism.
Actually, the situation is far more serious than racism.
I can remember times when police in America were reliable. They had themselves under control and saw their role as helpful to citizens and investigators of crimes. They took care not to bring charges against innocent people and to kill citizens without cause. Police would put their lives on line in order to avoid making a mistake in the use of their power.
Those times are gone forever. The police have been militarized, especially after 9/11, but even before. Police are taught to regard the public, especially any suspect or traffic offender as a potential threat to the police. The new rule taught to police is to apply violence to the suspect or offender in order to protect the police officer, and to question suspects only after they are safely secured, it they are still alive after being beaten, tasered, or shot.