“All of the border things that we’ll be building will be done right here in the good old USA by steel companies that were practically out of business when I came into office as president. And now, they’re thriving.” Later, he said, “the steel industry was almost dead.”

"Dead" is an exaggeration. Steel production has been in decline, as has the number of employees in the industry. But the metals industry still employed over 360,000 workers and produced 80 million tons of raw steel in the year before Mr. Trump took office.

At any rate, Mr. Trump continued, “we’ve already built a lot of the wall” and “renovated a tremendous amount of wall.” (The Trump administration has replaced some existing barriers with new barriers, and will begin constructing 14 miles of new wall in February. But to date, construction on his border wall has not started.)

Shutdown ownership and impact

In his first meeting about a shutdown with Representative Nancy Pelosi and Senator Chuck Schumer in the Oval Office last month, the president forcefully said that he alone would own the shutdown. On Friday, he was selling shares in it. “You can call it the Schumer or the Pelosi or the Trump shutdown,” he said. “Doesn’t make any difference to me. It’s just words.”

Could he reach a compromise with Democrats to end the shutdown by coupling wall funding with a pathway to citizenship for the young immigrants known as Dreamers? Mr. Trump responded that Democrats lost interest as soon as the United States Court of Appeals for the Ninth Circuit upheld an injunction against his administration’s termination of the Deferred Action for Childhood Arrivals program. (A deal on the program and to avoid an earlier government shutdown in early 2018 faltered last January, after Mr. Trump made vulgar remarks on immigration. The court ruled on the case in November.)

That was such a bad decision from the court, Mr. Trump asserted, that even his predecessor, “when he signed the DACA, with the executive order, made a statement to the effect, this isn’t going to work.” (President Barack Obama did not sign an executive order to implement the Deferred Action for Childhood Arrivals program. He announced it as a Department of Homeland Security policy in a speech in 2012. He did not say it would not work, but called it a “temporary stopgap.”)

For federal workers who may need a safety net or financial assistance as they go without pay, Mr. Trump said “the safety net is going to be having a strong border,” especially because government employees support his wall. (A recent poll of more than 1,400 by Government Executive suggests the opposite: most oppose the shutdown and the wall.)