Trump signs an executive order for border security and immigration enforcement improvements at the Department of Homeland Security in Washington.

Jan. 25, 2017 Trump signs an executive order for border security and immigration enforcement improvements at the Department of Homeland Security in Washington. Chip Somodevilla/Pool photo via Bloomberg News

A disturbing scene unfolded at the White House on Monday afternoon. A hook-and-ladder firetruck and a utility bucket truck pulled up to the South Portico and extended their rescue arms in the vicinity of the Truman Balcony.

Had the first lady finally decided to make a break for it?

Did President Trump need to be talked off the ledge after his latest poll numbers?

The real reason was every bit as fanciful: The Trump White House had invited the makers of the trucks — and manufacturers of all stripes — to bring their wares to Washington to show that Trump was making good on his promise to revive manufacturing jobs in America.

The president admired baseball bats and golf clubs, tried on a Stetson, asserted that the representative from an Omaha beef producer “wanted to kiss me so badly,” gave a thumbs-up from the driver’s seat of the firetruck and admired a Sikorsky helicopter. “I have three of them,” this champion of the little guy reported. Trump, whose businesses fill hotel rooms with mostly imported goods and whose daughter manufactures her clothing line entirely overseas, proclaimed this “Made in America” week.

(The Washington Post)

[Ivanka Inc. ]

That Trump would attempt to give the impression that he is leading a manufacturing revival makes sense: In the otherwise dismal new Washington Post-ABC poll, Trump’s handling of the economy is the only area in which he is viewed favorably by the public, by a narrow 43 percent to 41 percent.

But if Americans were to discover Trump can’t make good on his promise to lead a resurgence in manufacturing jobs— then, well, it might be time for him to call in a five-alarm blaze and ride that hook-and-ladder into exile at Mar-a-Lago.

[Poll finds Trump’s standing weakened since springtime]

The new poll finds that only 36 percent of the public approves of the job Trump is doing, the lowest at the six-month point in any presidency over the past 70 years, when modern polling began. Only 25 percent support him strongly. But, to paraphrase Trump’s remarks to the first lady of France, he is in such good shape — beautiful! — compared with where he would be if his supporters were to lose faith in his economic policies. Then, the bottom would drop out.

I asked The Post’s polling chief, Scott Clement, to run a regression analysis testing how views of the economy shape overall support for Trump when other variables such as party are held constant. The result was powerful: People who approve of his handling of the economy are 40 or 50 percentage points more likely to approve of him overall. While views of the economy closely correlate with partisanship, this means, all things being equal, that Trump’s overall approval rating should drop four or five points for each 10-point drop in views of his economic performance. Because Trump supporters are largely unconcerned with his personal antics, economic woes — not the Russia scandal or zany tweets — are what would doom Trump in public opinion.

The problem for Trump is many of his populist promises are starting to look fraudulent. Remember that Carrier plant in Indiana that Trump claimed to have saved? It’s reportedly beginning to lay off 600 people. The Boeing plant in South Carolina that Trump visited in February to showcase his fight for manufacturing jobs? Layoffs there, too. Trump denounced plans by Ford to move production of the Focus from Michigan to Mexico. Now Ford is moving the work to China instead.

As The Post’s Tory Newmyer reported, manufacturing employment hit a record low last month of 8.47 percent of overall employment. It has long been trending that way and is forecast to continue. Manufacturing wages rose less than the overall private sector.

[Finance 202: ‘Made in America’ week belies weak manufacturing numbers]

This isn’t primarily because taxes are forcing production overseas. It’s productivity: Manufacturers can produce twice as much in the United States as they did a few decades ago with a third fewer workers. Likewise, coal mining jobs aren’t leaving the country because of regulations, as Trump tells his supporters; the jobs have been lost to market forces in the form of cheap oil and gas.

The Congressional Budget Office, led by a Republican appointee, forecast last week that the economy would grow at just a 1.9 percent clip under Trump’s proposed budget, far less than the 3 percent the White House claims and the higher levels Trump alleges. The CBO also said the Trump budget would leave a $720 billion deficit in a decade, contrary to Trump claims.

So what happens if — and when — Trump’s core backers discover that they’ve been had: They’re losing health-care coverage and other benefits, while manufacturing jobs aren’t coming back and a Trump-ignited trade war is hurting U.S. exports?

He’ll need more than a hook and ladder to escape that disaster.

Twitter: @Milbank

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