Recently I’ve been looking for examples of national comebacks — nations that were plagued by turmoil, inequality and polarization, but that managed to get their act together and emerge stronger than before.

I’ve been especially interested in the way Britain revived itself between 1820 and 1848. Its comeback has some humbling lessons for us today.

Britain was roiled by economic and demographic changes. There were financial crises, bad harvests and a severe depression. There was crushing inequality. The average life expectancy nationwide was 40, but in the industrial cities of Manchester and Liverpool it was around 28. There were widespread riots and government crackdowns. In 1819, 1,206 “radicals” were given the death sentence, though only 108 of them were executed.

The nation responded to the turmoil both from the bottom up and the top down.

There were, first, a series of social movements: There was the Clapham sect. This was a group of evangelical leaders, arising from the general religious revival, that sought to eradicate slavery, spread the faith, discourage indebtedness, build Sunday schools, reform behavior and basically spread what we now call Victorian morality. ...