• The aftermath of hatred.

The man charged with killing 11 congregants at an American synagogue posted about his hatred of Jews on social media. And in the wake of the killings, our reporters found a flood of new anti-Semitic posts on Instagram.

It’s the latest evidence that social network companies never quite understood the negative consequences of their influence nor what to do about it — and that they cannot put the genie back in the bottle.

→ On the ground: Pittsburgh prepared for the first funerals. Above, a victim’s coffin. President Trump is visiting the city with the first lady and his Jewish daughter and son-in-law, despite critics saying he should stay away unless he changes his divisive tone.