Intelligens and culture. Black culture is violent and it is their fault. They glorify gangsters and think it is cool to hate police and keep silent on crimes. They are racist and hateful, blaming everybody but themselves. They are dindus.
If a black person is not like that he is ostracized as a Oreo, a black on the outside, white in the middle, a onkel Tom.
They kill more, rape more, rob more and you are so ignorant and stupid, you don't even blame them, so it just continues. This will end in a race war if black people keeps getting brainwashed into hating white people, and not changing their sick violence culture, and taking responsibility for their own actions. But maybe that is what you sick left wing apologetic retards want?
http://www.breitbart.com/big-government/2015/11/28/5-devastating-facts-black-black-crime/
http://www.amren.com/news/2015/07/new-doj-statistics-on-race-and-violent-crime/
https://infogr.am/Black-34991937313
Educate yourself and spreading your stupidity.