The Fourth of July week was bloody and heartbreaking. Even as Chicago celebrated a less violent holiday weekend than we had endured in previous years, such “success” was promptly followed by the police killings of Alton Sterling, a thirty-seven-year-old black man, in Baton Rouge after midnight on July 5, and Philando Castile, a thirty-two-year-old black man, in the Falcon Heights suburb of St Paul, Minnesota a day later.

The holiday week concluded with more horror: a mass shooting carried out by a lone gunman, Micah Xavier Johnson, who targeted Dallas police officers assigned to an anti–police brutality march. Loose talk of race war drifted through the ether and airwaves.

Unlike the phalanx of heavily armored police who routinely confront protesters in other cities, in Dallas many officers donned plain dress uniforms and did not wear flak jackets. In the end, Johnson killed five officers, and wounded six others. After an extended standoff, he was killed when police equipped a robot to deliver a bomb.