Is any conflict unsolvable? This author doesn’t think so.

Amanda Ripley does not like to think of any conflict as unsolvable. Her new book, “High Conflict,” reveals that progress is possible even in the most bitter, entrenched, and violent clashes. 

The genesis for Ms. Ripley’s book was the political divide in the United States. She began wondering how ordinary people become mired in extreme, yet commonplace, polarization. It’s the type of strife that keeps people awake at night, encourages them to start flamethrower tirades on Twitter, or entices some to cut off relationships with friends and family. In what she terms high conflict, one imagines adversaries as evil and less than human. 

Ms. Ripley, an investigative journalist for The Atlantic, went searching for examples of people and communities who had been stuck in high conflict and found a way out. That quest led her to meet with Democrats in New York City and Republicans in rural Michigan. In the rival gang territories of Chicago and in civil war-torn Colombia, Ms. Ripley