The stunningly quick collapse of support for the Confederate flag has been told largely through the public pronouncements of one governor, Nikki R. Haley of South Carolina, who persuaded the legislature to reconsider the flag’s prominent perch on the capitol grounds. But behind the scenes, powerful forces — capitalism, Christianity, social media, college sports and a Republican Party eager to extricate itself from the past — were converging. Within five days, decades of resistance in South Carolina, a state that had held fiercely to its Confederate identity, fell away.

Some of it was a result of simple demographics, as the aging white leaders with the deepest attachment to the banner found themselves wielding less sway among modern bases of power. The legislature is increasingly drawn from a younger generation, whose politics were forged well after the battle against civil rights and whose members are more solicitous of the state’s business class than its sons of the Confederacy. On social media, prominent black thinkers shaped and dominated a conversation about why the flag must go, setting off a river of retweets and reverberations, while flag supporters trying to counter the argument were shouted down.

And, in the country’s most churchgoing region, Christianity played a potent role. White worshipers described themselves as pained by guilt and moved beyond measure after watching relatives of the nine victims in Charleston deliver an unexpected message, distilling the essence of Christianity at a bond hearing for the suspect: We forgive.

The consensus among the state’s establishment to remove the flag came about, many civic leaders said, also because of what did not happen: There was no violent reaction, which made the old antagonisms harder to summon. No swarms of outsiders flooded the State House. Instead, the small state and the small city of Charleston seemed proud of their comportment, and eager to atone for the hurt.

Defenses Dry Up

No one knows the arguments against removing the Confederate battle flag better than State Senator Paul Thurmond, a Republican who is a son of Strom Thurmond, the longtime United States senator from South Carolina and a segregationist candidate for president. Just after the killings in Charleston, he began to rehearse them.