A big Ohio steelmaker has agreed to pay $1.4 billion in stock and cash for ArcelorMittal USA’s 19 steel mills and iron mines, including plants in Conshohocken and Coatesville, in a deal that puts much of the American steel industry back under U.S. control.

The purchase by Cleveland-Cliffs is for the U.S. steel mills collected since 2005 by London billionaire Lakshmi Mittal and his European companies. This and other acquisitions will transform the Ohio company into North America’s largest maker of the flat-rolled steel used in everything from cars to appliances, with 25,000 employees, $17 billion in yearly sales, and a large debt.

Pittsburgh-based U.S. Steel, in contrast, has 30,000 workers, but had only $13 billion in annual revenue last year.

“Our success will not come from lower prices. It will come from quality, the ability to deliver on time," and the use of “green” technologies, said CEO Lourenco Goncalves a dynamic immigrant from Brazil whom some have compared to Tesla founder Elon Musk.

The deal to return so many steel mills to U.S. ownership comes just a day before the first presidential debate is scheduled for the buyer’s hometown of Cleveland, after a campaign in which the candidates have argued the causes and cures of the long-term decline of U.S. steelmaking and other heavy industries, said J. Chris Rooney, president of Vanness Co., a Florida consulting firm.

He said ArcelorMittal and other companies had failed to take advantage of the Trump administration’s restrictions on steel imports. Rather than producing high-quality steel, critics say, too many American mills have continued to make cheap steel for construction and other basic uses. (Rooney notes that ArcelorMittal’s Philadelphia-area mills, by contrast, produce high-specification structural plate and beam steel.)

That forced U.S. trade adviser Peter Navarro to reverse the administration’s protectionist policy and permit imports to supply U.S. factories.

Goncalves will now have the mills to turn top quality iron ore into higher-end products for U.S. industry, Rooney said.

In each of the last two years, ArcelorMittal U.S. sales topped $10 billion, with around $700 million in profits.

Locally, the sale includes the historic Lukens steelworks on the Brandywine in Coatesville, which employs 638, and the old Alan Wood Steel plant on the Schuylkill in Conshohocken, which employs 126.

The Coatesville plant produces steel from scrap in an electric arc furnace and can make up to 900,000 tons annually. Working together, the Coatesville and Conshohocken plants make some of the “widest, thickest and heaviest steel plates in the industry” to build high-rise buildings and ships, the company said.

In a conference call Monday with investors and analysts, Goncalves noted Cleveland-Cliffs had been a longtime iron supplier to ArcelorMittal’s mills, making it a known quantity.

“This takes us where we need to be in this competitive and increasingly quality-focused marketplace,” he said.

With more plants, his company can borrow more money to expand or update as needed, he said.

In the call, Goncalves spoke highly of the seller’s unions, noting that besides steelworkers, they include members of machinists and auto workers units. But he also said he hoped to cut expenses by $50 million in 2021 and a further $100 million the following year, and would review each new plant before deciding whether to invest.

The United Steelworkers “has had a good working relationship with Goncalves and Cliffs, and we expect that will continue,” Tom Conway, the union’s international president, said in a statement.

The deal caps rapid expansion by Cleveland-Cliffs, which was best known as the nation’s oldest iron ore-mining company before its $1.1 billion all-stock takeover in March of another big steelmaker, Cincinnati-based AK Steel, and its mills, including one in Butler, Pa.

It also comes amid a slump in industrial sales that has made companies cheaper to buy — and a change in technology by which Cleveland-Cliffs is burning cheap, cleaner U.S. natural gas to make steel rather relying on smoky, coal-based coke.

ArcelorMittal, controlled by members of India’s Mittal family, had previously consolidated plants built generations ago by Bethlehem Steel, Inland Steel, and other U.S. steelmakers after the closings of famous works at Bethlehem, Pa., and Sparrows Point near Baltimore. It also consolidated more modern complexes such as Indiana’s Burns Harbor, near Chicago.

Cleveland-Cliffs is acquiring ArcelorMittal without taking on any additional debt, other than pension obligations. The deal is to close in the next two months, pending regulatory approval.