This is the result of policies, not some inevitable law of nature, not technological change. This means we can do something to make things better. But our government will not confront China's currency manipulation, and our trade and tax policies encourage deindustrialization, taking advantage of low wages and the absence of environmental, safety and other regulations in countries where people do not get much of a say, like China and Vietnam.
Selling the same goods but paying less to produce them means there is a bunch of extra cash in the pockets of U.S. "investors." But they do not reinvest here because the resulting unemployment and drop in wages causes slack demand. And on it goes as the world's imbalances grow and grow.