The onetime dynamo is fighting to revive a takeover by Nippon Steel. Other tie-ups could also face obstacles, and going it alone could force cutbacks.

United States Steel Corp. CEO David Burritt in an interview with CNBC appealed to President-elect Donald J. Trump to rescue the Pittsburgh-based company's $14.9 billion acquisition by Nippon Steel Corp.

Supporters of the sale of U.S. Steel to Japan’s Nippon Steel are still hopeful that Donald Trump could revive the nearly $15 billion dollar acquisition.

Donald Trump’s increasingly strident approach to relations with Canada is provoking fear about the potential consequences north of the border and questions about just how serious the U.S. president-elect actually is.

Among the most senior officials in Ottawa, there is a document circulating that outlines specific details about how Canada could retaliate against Donald Trump’s tariff threat.

"President-elect Trump has proposed various tariff plans at various times on the import of foreign goods, including a 10% blanket tariff on all imports, a 60% tariff on Chinese goods and 25% tariffs on goods from Mexico and Canada," says Ben Johnston, chief operating officer of Kapitus, a financial services firm that focuses on small business.

U.S. Steel and Nippon Steel said on Monday that it is suing over President Joe Biden's decision to block its sales agreement and a domestic competitor and union over their actions to scuttle the deal.

Biden is set to announce that he'll block the takeover of U.S. Steel by Japan's Nippon Steel, thereby fulfilling one of Trump's pre-election promises.

Canada is looking to target American steel, ceramics, plastics and orange juice with retaliatory tariffs in response to threats of hefty duties on Canadian imports by the incoming Trump administration.

A senior official says Canada is looking at putting retaliatory tariffs on American orange juice, sinks, toilets and some steel products if U.S. President-elect Donald Trump goes ahead with his threat to impose 25% on all Canadian products.

Logical, but not perfect. The Wall Street Journal pointed out that a Cliffs-U.S. Steel combination "would control 100% of U.S. blast furnace production, 100% of domestic steel used in electric-vehicle motors, and 65% to 90% of other domestic steel used in vehicles."