I live in a central California farmhouse built by my great-great-grandmother in the 1870s. But if the clapboard house looks more or less unchanged from its earliest photographs taken in the 1920s, the world down the road is unrecognizable.

In 1890, my grandfather was born here. Eighty years later, he still related to us his grandmother's wild stories of post-Civil War Missouri. She along with her son, my great-grandfather, had come west from there on the new railroad. When they arrived, they built a shack not far from my front door.

Disease, drought and gunfights over water were the existential challenges that lapped around the early farm. For 50 years until the advent of running water, electricity and gas engines, the household's members worried whether or not they would eat.

My grandfather added a modern kitchen in the 1940s. And he faced more complex challenges than the elemental hunger and illness of his predecessors, such as trying to sell raisins for $30 a ton during the Depression.

The house and farm were saved in the 1970s by my parents' jobs in town. Before they died, they worried for us, the more affluent and leisured, about globalization that crashed fruit prices and about rising taxes, along with more government paperwork and requirements.

For us, the more privileged fifth generation that added another bathroom and enlarged the yard, the challenges were more postmodern — massive illegal immigration, the spread of rural meth labs, or the end altogether of family farms like ours.

But through all these cycles of American history, the populists in the house — whether reciting William Jennings Bryan's 1896 "Cross of Gold" speech or mounting Edwin Markham's 1899 poem "Man With a Hoe" on the staircase, where it still hangs — were at least able to make sense of the world along recognizable fault lines.

Democrats mostly were union people, desperate farmers or the less affluent who wanted greater government help for their weak farm prices, minimum wages and bleak retirements. I see them still in faded brown pictures, leaning in their overalls against Model-Ts in our driveway.

More affluent Republicans in town believed the less government and taxes, the better. Democrats were thought of as naifs for promoting democratic idealism abroad; conservatives were hardheaded realists who counseled us to keep our distance from a scary world.

Enemies overseas wore jackboots and advanced awful ideologies — fascism, Nazism and communism — that were European-inspired and thus at least somewhat familiar.

All those conventional divides, big and small, I remember being rehashed in our dining room in the 1960s as generations of dead ancestors stared down in sympathetic silence from their sepia portraits.

But my children, the sixth-generation inheritors of the house, are facing a surreal world. The new leaders of the left, not much different in their lifestyles from those on the elite right, are now almost all multimillionaires. Their populism focuses on everything from gay marriage and unrestricted abortion to stopping Arctic oil exploration.

Jihadists don't wear uniforms. Even hostile countries that subsidize such terrorists deny doing so. Nazis and Stalinists never toppled an American office building; Islamists with far fewer resources have. And in a world of miniaturized weapons and easy global travel, they have a better chance of repeating their carnage than any of our earlier, more recognizable enemies.

It was once easy to rail at the interest charged by the local land bank or the freight rates of the railroad. But how do you compete against high-quality Chilean grapes in the local mega-store? Is the Wal-Mart, now only two miles distant, pernicious for destroying local hardware stores, or beneficial for providing low-cost goods for the legions of poor who prefer it — or neither?

But the greatest difference is that those first four generations who lived and died in this house shared a certain tragic vision of man's limitations. Perhaps they lost too many crops before harvest. Or they grew to assume that optimistic weather reports and upbeat cooperative newsletters were hardly to be trusted as "intelligence." They considered the choices in their many wars only between bad or worse, and that the Americans who fought them did not have to be perfect to still be good.

Now this relic of a house has a TV dish on the roof and automatic garage doors. Yet otherwise it must look about the same as when someone, whom I seem to know but never saw, built it right after the Civil War. But while we can still recognize it as the familiar solid house of old, I wonder whether it would say the same of us now inside.