But keeping this promise will be difficult, as Mark Muro, a senior fellow at the Brookings Institution, recently argued. That’s because American workers may be struggling, but American factories are not.
The relationship between factories and workers has changed over the past decades, and it’s unlikely to go back. Over the past 35 years, the United States shed about 7 million manufacturing jobs. And some industries, such as textiles and apparel, have disappeared almost entirely.
Yet American factories actually make more stuff than they ever have, and at a lower cost. Manufacturing accounts for more than a third of U.S. economic output — making it the largest sector of the economy. From that perspective, it’s hard to argue that American manufacturing today is anything but a success.
The issue is that the fortunes of factories themselves and of manufacturing workers have diverged, as Muro’s chart below shows. U.S. factories 
now manufacture twice as much as they did in 1984, with one-third fewer workers, according to the Federal Reserve.
