Some people think that dialogue and debate can help the United States defeat its current tribalism. If only we could calmly talk about our differences, the argument goes, we would reach some compromise. But not all disagreements are bridgeable. The Union and the Confederacy did not resolve their differences through dialogue; it was a civil war that put an end to slavery. Jim Crow laws were defeated through mass protests and civil disobedience. Schools were desegregated though a Supreme Court decision, which had to be implemented with the help of the National Guard. The Chinese Exclusion Act was repealed as a political necessity during World War II. Some fights are not talked away; they are, in the end, either won or lost.

This is not to say that tribal impasses of the moment can’t be broken. But it is generally not a good idea to expect people on the receiving end of brutal policies — like families broken apart by police violence, immigration raids, travel bans or anti-L.G.B.T. discrimination — to hash out a compromise over sweet tea. “Maybe we pushed too far,” Barack Obama is quoted as saying in a new memoir by Benjamin Rhodes, one of his closest aides. “Maybe people just want to fall back into their tribe.” What the ever-compromising Obama doesn’t consider is that resolution sometimes requires pushing even further.