When Donald Trump was inaugurated, by most measures, the United States was the strongest major economy in the world. Growth was robust, unemployment was just above a historic low, inflation had fallen to a manageable level, and productivity — the elixir of economics — had picked up. Trump took this booming economy and upended it with massive tariff hikes. Has anything like this ever been done before? Well, nothing quite as self-defeating, but the Smoot-Hawley tariffs were also imposed after a decade of heady growth. That story is worth recalling because there are startling parallels to today’s situation.

We remember the 1920s as the “Roaring Twenties,” and in economic terms, it’s apt. The annual growth rate for the decade was over 4%. Unemployment stayed low for most of it. Revolutionary innovations defined the period. Henry Ford perfected the mass-production systems that would define modern manufacturing for decades. Just as the 1990s and 2000s were celebrated for creating a new economy, that was the feeling about the ’20s.

But there was another story about that decade — about the hollowing out of a core American industry, of jobs being shipped abroad and of the loss of the soul of the country. Agriculture had been at the heart of the American economy, accounting for most of the workforce until the late 19th century. Even by 1900, 40% of the American workforce labored in the agricultural sector. By 1920, more than half of the country had moved into cities, and only 26% of Americans worked in agriculture. The American way of life was in peril.

America’s first great populist movement was birthed in the late 19th century in response to the decline of agriculture. It briefly captured the Democratic Party, with the fiery populist orator William Jennings Bryan becoming the party’s nominee for president three times. By the 1920s, the movement had weakened and moved into parts of both the Democratic and Republican parties. It gained ground as farming was hit hard during the 1920s.

By 1930, in the wake of the 1929 stock market crash and economic slowdown, congressional Republicans from farming states were adamant that farmers needed support. They allied with legislators who wanted to protect American industry and produced what they might have described as a “big, beautiful bill” that raised tariffs substantially on a variety of products, industrial and agricultural.

More than 1,000 economists wrote an open letter to President Herbert Hoover urging him not to sign the bill because it would raise prices, lower the standard of living and hurt American exports. But in those days, Congress was the leading branch of government on trade (and mostly everything), and Hoover reluctantly signed the bill into law. (Hat tip to Douglas A. Irwin for his superb book on all this.)

The global reaction then was similar to now. Countries were outraged, many retaliated, and those with the closest economic ties to the U.S. responded the most forcefully. The tariffs upended relations with America’s northern neighbor, Canada. The outbreak of protectionism infuriated Canadians, who retaliated strongly with tariffs of their own. Canadian nationalism surged, and in the elections that year — an eerie parallel to this year — the party that was seen as most authentically anti-American won.

Scholars disagree on the effects of the Smoot-Hawley tariffs. Few now argue, as they once did, that these tariffs caused the Great Depression — but many believe they exacerbated it. What no one disputes is that they failed to preserve American farming jobs. Today, agriculture employs about 1% of the American workforce.

In the 20th century, we looked back fondly on farming as special. It was important to grow things. And so we taxed the entire country to protect farmers. In the 21st century, we have similar views about manufacturing. It’s important to make things. So we are taxing the entire country, more than 80% of which works in services, to subsidize the 8% that works in manufacturing. It is fundamentally a politics of nostalgia, looking fearfully at the past rather than confidently at the future.

Email: fareed.zakaria.gps@turner.com.