When it comes to the U.S. steel industry and international trade, the talk is usually about imports.

The focus is on which countries are shipping steel to the United States, at what price, if they've gotten subsidies, are dumping it below price, and whether the U.S. government will impose tariffs meant to deter dumping. Domestic steelmakers like U.S. Steel, Chicago-based ArcelorMittal USA and Fort Wayne's Steel Dynamics have pursued a number of trade cases against foreign steelmakers as steel layoffs have mounted and mills have been idled.

But U.S. steel mills also export metal to foreign countries. For instance, in 2011 ArcelorMittal's Burns Harbor steel mill sent 18,000 metric tons of Northwest Indiana-made steel through the Port of Indiana-Burns Harbor to Macedonia in southeastern Europe.

Most of the exports, however, go to North America neighbors in Canada and Mexico.

"While the majority of our domestic steel production stays in the United States, ArcelorMittal does ship to locations throughout North America from our U.S. facilities," ArcelorMittal USA spokeswoman Mary Beth Holdford said.

The main reason why U.S. steel gets exported is that the auto industry is one of its biggest customers, and automotive plants are spread across North America. About 27 percent of steel shipments last year went to the automotive industry, according to the American Iron and Steel Institute.

Fiat Chrysler, Ford, General Motors, Honda and Toyota operate 16 automotive plants in Canada, employing 120,000 workers and producing $83 billion worth of goods. Ford has announced plans to move all its small car production to Mexico because it's hard to turn a profit on such a low-margin vehicle when they're made in the United States, according to Ford CEO Mark Fields.

In anticipation of higher demand, ArcelorMittal recently restarted a blast furnace at ArcelorMittal Indiana Harbor West in East Chicago to produce raw metal that will be finished at AM/NS Calvert in Alabama for auto plants across the South and in Mexico. ArcelorMittal Chairman and CEO Lakshmi Mittal said during the company's third quarter conference call that much of that steel made in East Chicago would end up in auto plants in Mexico.

Exports to Mexico and Canada account for nearly 90 percent of all steel exports out of the United States, according to the American Institute for International Steel.

Canada bought 389,371 net tons of steel made in the United States in September, while Mexico imported 324,661 net tons of steel made in the United States. America also exported 19,364 net tons to the European Union in September, a 9.5 percent increase over the same period in 2015.