Income inequality has surged as a political and economic issue, but the numbers don’t show that inequality is rising from a global perspective…

The finding comes from a recent investigation by Christoph Lakner, a consultant at the World Bank, and Branko Milanovic, senior scholar at the Luxembourg Income Study Center. And while such a framing may sound startling at first, it should be intuitive upon reflection.

The economic surges of China, India and some other nations have been among the most egalitarian developments in history.

Of course, no one should use this observation as an excuse to stop helping the less fortunate. But it can help us see that higher income inequality is not always the most relevant problem, even for strict egalitarians. Policies on immigration and free trade, for example, sometimes increase inequality within a nation, yet can make the world a better place and often decrease inequality on the planet as a whole.

International trade has drastically reduced poverty within developing nations, as evidenced by the export-led growth of China and other countries. Yet contrary to what many economists had promised, there is now good evidence that the rise of Chinese exports has held down the wages of some parts of the American middle class. This was demonstrated in a recent paper by the economists David H. Autor of the Massachusetts Institute of Technology, David Dorn of the Center for Monetary and Financial Studies in Madrid, and Gordon H. Hanson of the University of California, San Diego.

At the same time, Chinese economic growth has probably raised incomes of the top 1 percent in the United States, through exports that have increased the value of companies whose shares are often held by wealthy Americans. So while Chinese growth has added to income inequality in the United States, it has also increased prosperity and income equality globally.

The evidence also suggests that immigration of low-skilled workers to the United States has a modestly negative effect on the wages of American workers without a high school diploma, as shown, for instance, in research by George Borjas, a Harvard economics professor. Yet that same immigration greatly benefits those who move to wealthy countries like the United States. (It probably also helps top American earners, who can hire household and child-care workers at cheaper prices.) Again, income inequality within the nation may rise but global inequality probably declines, especially if the new arrivals send money back home.

From a narrowly nationalist point of view, these developments may not be auspicious for the United States. But that narrow viewpoint is the main problem. We have evolved a political debate where essentially nationalistic concerns have been hiding behind the gentler cloak of egalitarianism. To clear up this confusion, one recommendation would be to preface all discussions of inequality with a reminder that global inequality has been falling and that, in this regard, the world is headed in a fundamentally better direction.

The message from groups like Occupy Wall Street has been that inequality is up and that capitalism is failing us. A more correct and nuanced message is this: Although significant economic problems remain, we have been living in equalizing times for the world — a change that has been largely for the good. That may not make for convincing sloganeering, but it’s the truth.