Too much anger too often leads to violence

The CEO of a large health insurance provider was shot dead on the sidewalk in front of his New York City hotel in a planned killing and 57,000 people posted laughing emojis on the company’s Facebook page.

When did murder become funny?

Days after the Dec. 4 killing, the tone turned even uglier. “Wanted” posters started appearing in New York City, glued to light poles and traffic control boxes at street corners. But these posters were not searching for the murderer; they were threatening more violence against health care executives.

“Health care CEOs should not feel safe,” the posters said. One...