Are trade wars class wars? The importance of trade-induced horizontal inequality
从理论和实证上论证了贸易引发的水平不平等（即相同收入水平的工人之间的不平等）的重要性，发现美国贸易冲击的福利变化中超过99%的差异来自同一收入阶层内部，挑战了“贸易战是阶级战争”的流行观点。
What is the nature of the distributional effects of trade? This paper demonstrates conceptually and empirically the importance of “trade-induced horizontal inequality,” i.e. inequality that occurs among workers with the same level of earnings before the trade shock. This type of inequality does not affect the income distribution but generates winners and losers at all income levels. To quantify the horizontal inequality and changes in the income distribution induced by trade in a data-driven way, we develop a characterization of the welfare impacts, governed by simple and intuitive statistics of labor market and consumption exposure to trade. In the U.S., we find substantial heterogeneity in exposure and thus in the welfare effects of trade shocks across workers. Over 99% of the variance of welfare changes from trade shocks arises within income deciles. These findings run against a popular narrative that “trade wars are class wars.”