Thirty years ago, same-sex marriage was far from a reality.
In fact, Sasha Issenberg says it wasn’t even a real priority to most of the LGBT community then. But one Honolulu court case and a wave of religious opposition later, and gay marriage is a given today.
How did it go from unthinkable to culturally ubiquitous in a quarter-century?
Issenberg has written the definitive history of it in his new book, "The Engagement: America's Quarter-Century Struggle over Same-Sex Marriage."
He said it all began long before it became a political issue in the 1990s. The Show spoke with him to learn more about the cultural shift.