A longstanding and pernicious myth is that major corporations and "globalists" – apparently Donald Trump's pejorative term for wealthy individuals – are the primary beneficiaries of America's 70-plus year, bipartisan trade liberalization efforts. The losers, according to this myth, are America's poor and low-skilled workers, who have supposedly experienced widespread job loss due to increased foreign competition.

While some might find this theory appealing, the notion that robust middle- and lower-class economic gains are right around the corner if America just turns inward happens to be spectacularly wrong.

There is no question that America's middle and lower classes have benefited from our trade liberalization. Through the widely accepted principle of comparative advantage in our trade policies, productivity has surged and prices have declined. Lower prices save the average American family thousands of dollars a year on goods they consume, raising the standard of living through enhanced purchasing power.

Summarizing a 2014 study by Pablo D. Fajgelbaum and Amit Khandelwal, the New York Times stated their work found "that international trade had lifted the purchasing power of lower-income American households, at the 10th percentile of the income distribution, about 62 percent. For wealthy households, at the 90th percentile of the income distribution, the power increase was 3 percent." In other words, lower-income Americans have experienced outsized gains from trade agreements because they spend a greater percentage of their income than wealthier peers on the types of goods that declined the most in price.

Not only do lower priced consumer goods resulting from trade agreements benefit American families, lower priced inputs make American companies more competitive by lowering their production costs. It is estimated that between 50 and 60 percent of goods imported into the U.S. are intermediate products used in the production process. The businesses that use these inputs employ millions of Americans and would be jeopardized by higher manufacturing costs.

The reality is that, thanks in part to robust foreign trade, U.S. manufacturing output is at a historic high. Though it's true that manufacturing employment has declined, the overwhelming majority of this trend can be attributed to automation and productivity gains. Regrettably, misguided politicians and other protectionists too often use globalization and trade agreements as a scapegoat, rather than acknowledging this reality.

But who would bear the brunt of greater protectionism? Trump and other protectionists often imply trade is a zero-sum game: If China's economy is growing, for instance, America is losing. But boil down this overheated, misleading rhetoric and consider how a tariff increase would work in practice. Simply put, like a sales tax, it would amount to a regressive financial burden on goods and services consumed by American families and businesses. That hidden tax would in essence subsidize the very types of politically-connected insiders the protectionists rail against.

After Trump suggested a 45 percent tariff on imports from China and Japan and a 35 percent tariff on imports from Mexico, economists with the National Foundation for American Policy found that the effect of such policies would devastate lower income Americans. Over a five year period, the study found, U.S. households in the lowest 10 percent of annual income would pay up to 18 percent of their after-tax income, or nearly $4,700 more, for the items they consume. New tariffs of this magnitude would not be a cakewalk for the middle class, either; the average American household – about $56,000 in annual after-tax income – would be hit with a tariff burden of a little more than $11,000 over a five year period.

Not only would middle- and lower-income Americans face higher regressive taxes from tariffs, job loss would surely follow – impacting Americans all over the country. A new Peterson Institute study found that private sector job loss could reach 5 percent in heavily trade-dependent states like Washington, Massachusetts and California if new tariffs were implemented.

While globalization has been a terrific success for America and the rest of the world, it is true that small pockets in the United States have been slower to adjust to "trade shocks," e.g., China's ascension into the World Trade Organization in 2000, than previously believed. This classic case of diffused benefits and concentrated costs was highlighted earlier this year in a study by David Autor, Gordon Hanson and David Dorn, all prominent labor economists. Their paper, though, doesn't refute the 200 year economic consensus in favor of free trade.

Summarizing the study, the New York Times noted, "Mr. Autor, like most economists, is still persuaded of the long-established benefits that global trade confers on the economy as a whole." The authors argue that the United States needs to do a better job of speeding up the adjustment after trade shocks. Smarter labor market policies can address this problem far better than protectionism.