In 1974, the post-Watergate Republicans were toxic beyond measure, and everyone knew they were finished utterly. In one memorable interview at the time, a Teamster leader complained that his union was always being linked to the Mafia, and that was OK, but any suggestions that the Teamsters had Republican ties were just hitting below the belt. Hoping to escape the Republican shipwreck, conservatives floated the idea of a new and untainted third party. But then in 1976, Gerald Ford performed reasonably well against Jimmy Carter, and in 1980, Reagan won the first of a series of triumphs for himself and his party. Reagan’s victory in 1984 remains one of the greatest electoral wipe-outs in US history.

Democrats were equally doomed forever in 1984 and 1988, until in 1992, they weren’t. Following Obama’s first election, a European friend was wondering how the US would be able to cope without a second party to provide an opposition. The Republicans had so obviously been crushed totally, so that they ceased to matter. Well no, I said. Come back in 2010, and I will run for Congress in the liberal bastion of Berkeley, as a Republican, and I’ll win. Well, not Berkeley perhaps, but 2010 really did witness an epic near-sweep by Republicans.

The US system is extraordinarily generous at giving losers a second chance, and in a remarkably short time. And a third chance, and a fourth. A party finished forever? In electoral politics, ‘forever’ tends to run about two years. Forever changes.