Our civic and political discourse is replete with metaphors.

We avoid having to swallow a bitter pill by instead kicking the can down the road. Desperate candidates throw a Hail Mary pass. Sensitive souls learn that if they can’t take the heat, they should get out of the kitchen. A good prosecutor can get a grand jury to indict a ham sandwich.

Sometimes metaphors are used to express a political idea with verve, as when our nation of assimilating immigrants is dubbed a melting pot, or when John Roberts said his job on the Supreme Court would be to call balls and strikes. But metaphors are also invoked for more than style. A deft metaphor advances an argument — sometimes a highly dubious argument. To say the poor should get a larger slice of the pie is to imply that wealth is limited and someone should redistribute it. If American officials speak of pressing the Russia reset button, their message is that better relations with Moscow are primarily a matter of American will. Insist that illegal immigrants must go to the back of the line and you are contending that they had a legal option but chose to ignore it.

Of all the arguments we advance by metaphor, perhaps none is as potent as war. When Lyndon Johnson, unveiling an array of programs to assist the poor, declared a War on Poverty, he was telling the nation that it had no higher priority. When Jimmy Carter told the nation that curtailing energy use was the moral equivalent of war, his implicit argument was that American independence was at stake.

Consider another war metaphor — one employed so matter-of-factly that it has indelibly shaped public thinking: trade war.

Talk of trade wars is hardly new, but under Donald Trump, trade-war rhetoric has become ubiquitous. In speeches and on social media, he repeatedly approaches trade in terms suited to a grim international conflict — a struggle for dominance among nations in which there must be winners and losers.

“When a country (USA) is losing many billions of dollars on trade with virtually every country it does business with, trade wars are good, and easy to win,” Trump tweeted in March. Last month he put it even more sharply: “When you’re almost 800 Billion Dollars a year down on Trade, you can’t lose a Trade War! The U.S. has been ripped off by other countries for years on Trade.”

For centuries, economists have pointed out the destructive folly of tariffs and other trade barriers. Tirelessly they explain that a trade deficit is not a defeat, just as a shopper’s “deficit” with a department store is not a defeat. They implore policymakers to see that trade restrictions always impose more costs on a country’s economy than any benefits they generate. They highlight the ways in which protectionist tariffs make many consumers poorer in order to make a handful of producers richer — and how even the intended beneficiaries often end up worse off.

But data and common sense are no match for the seductive metaphor of trade as warfare.

Many Americans will say they favor free trade, but then add the caveat that it must be “fair trade” as well. They feel the tug of national resentment when the president demands: “Are we just going to continue and let our farmers and country get ripped off? Lost $817 Billion on Trade last year. No weakness!” They may not share Trump’s confidence that trade wars are “easy to win,” but they agree that other countries’ protectionist measures are a form of belligerence that cannot just be ignored.

The evidence is piling up that the impact of Trump’s retaliatory trade penalties has been falling hardest not on foreigners, but on Americans. Yet when the president indignantly declares that America is being victimized by its trading partners, much of the nation nonetheless nods approvingly. In a new survey, the Pew Research Center found that while 49 percent of respondents thought higher tariffs would be damaging, fully 40 percent said they would do more good than harm.

All of this comes from thinking of trade as metaphorical warfare — as an economic struggle pitting nation against nation.

That’s a great fallacy. Nations don’t trade with each other. We speak as if they do out of habit and convenience, but it’s not true. The United States and Canada are not competing firms. America doesn’t buy steel from China, and China doesn’t buy soybeans from America. Rather, hundreds of individual American companies choose to buy steel from Chinese mills and fabricators, and hundreds of Chinese-owned firms make deals to buy soybeans from far-flung American growers. Unlike wars, which really are fought by nation against nation, international trade occurs among countless sellers and buyers, all acting independently in their own best interest.

Tariffs don’t punish countries. They punish innumerable consumers, wholesalers, importers, exporters, farmers, manufacturers — the myriad discrete actors whose choices and preferences are the true substance of international trade. To those individuals, national trade deficits and surpluses are irrelevant. They aren’t competing — they’re cooperating. Buyers and sellers aren’t in conflict with each other, let alone with each other’s countries.

On the contrary: By doing business together, traders create wealth and connections, knitting the world together in mutual interest, making the planet more harmonious.

Trade war is an insidious term. The metaphor notwithstanding, trade isn’t war. It’s peace.

Jeff Jacoby is a columnist for The Boston Globe.