The companies said they had entered into an agreement with the U.S. government to alleviate any national security concerns.

The deadline for consummating the deal between U.S. Steel and Japan-based Nippon Steel is less than a week-and-a-half away, but hardly any more details of it have been made public since Donald Trump’s triumphal visit to West Mifflin late last month.

SEOUL — For corporate Japan, America’s treatment of its steel industry has been one blow after another. First, there were the objections to Nippon Steel’s takeover of its U.S. rival ...

For Japan and many other countries, the vulnerability that comes with relying on U.S. markets has become startlingly clear. First came tariffs on Canada, China, and Mexico. Then, in February, the administration introduced a 25 percent tariff on steel and aluminum (this week,