Why is black skin viewed as a weapon?

Credit: CC0 Max Pixel

One of the leading causes of death for young black men, is police brutality. Young black men in their mid to late 20’s have about a 1 in 1000 chance of being killed by police (source needed). For many of them they are murdered while they are unarmed and are committing no crime. However, we can see time and time again white mass shooters being taken alive in the most difficult of circumstances. Yet while police are obviously capable of taking armed suspects into custody, they somehow lose that ability for even unarmed “suspects” when they have darker skin. After police officers murder innocent black men they are rarely penalized for it and in some cases communities rally behind them to support them. In this we can see how little our country values our black men because they are vilified even after becoming a victim in order to excuse the officer that killed them. Many police officers claim they felt their life was in danger when they murdered black men but in a lot of these cases black men posed no threat to the officers. These occurrences prove that police officers fear black men in general more so than armed white men. In which case, how can we trust a system than sees dark skin as a weapon?