Voters are in a bad mood. Again. We are routinely (and justifiably) frustrated with our politicians, but “throwing the bums out” doesn’t seem to change much. And we are all bracing for another anger-pageant that will stomp through American life for the next 13 months until election day.

A forgotten moment in our history suggests that the way out of a bad political mood is not more rage, but a new political perspective. Around 1900, after years of anger at …