As I grew up, I started to see the narrative pattern: Democrats were going “extinct” in 1972 with Richard M. Nixon’s landslide. Republicans were “finished” after Watergate and the 1976 election. In 1984, Democrats were really “doomed” this time, wiped out by the “Reagan Revolution.” Of course, the way Republicans are acting today means they will inevitably lose power, and for a very long time — an exile they will richly deserve.

But neither party will disappear because the American center — that great lump of us clustered around the middle — always holds. Where the center is, exactly, moves over time — we changed the world by embracing same-sex marriage, for example — but it never goes away. That lump is our national ballast. To survive, our two political parties compete for that center, forcing them to change as we do. They regularly miss the mark, which is why the parties, not the United States, suffer repeated near-death experiences, always followed by miraculous revival.

When I was a kid, the United States didn’t come apart. It won’t now.