Dear Editor:

A white police officer calmly kills a handcuffed black man, forcing his knee into the other’s throat until he dies. This was not a rare example of casual and racist police brutality. It happens in every large American city more times than we dare to record.

But in the midst of our horror, grief and guilt, something hopeful is starting to glimmer Those outraged by this willful murder have arisen in such numbers and with such rage that the powers that be cannot sweep it under the rug,...