It was the most perplexing speech of Donald Trump’s career. 

Watching the 45th president deliver an address to Congress mercifully free of vitriolic attacks and short on egocentric nonsense prompted the obvious question: In what storeroom at Mar-a-Lago have they been hiding this version of Donald Trump?

We might have to wait for the White House memoirs to get the full story of how Trump was convinced to chain himself to a teleprompter and to avoid both refighting old wars and launching new ones. Of course, since the overnight verdict on the speech was positive, we will soon be treated to predictable leaks of credit-claiming by Trump insiders.

Normally, a successful address to the Congress would set the tone for the next few months on Capitol Hill and move opinion polls. But Trump is so omnipresent and so mercurial that the lasting effects of a single speech might be more evanescent than usual. Trump will always retain the ability to change the mood in Washington with a single intemperate tweet.

Critics have stressed many of the missing elements in the Trump speech, such as Russia, Syria, and the ludicrous notion that Mexico could be bludgeoned into paying for a border wall. But, in policy terms, the most striking omission was a full-throated sermon on the dangers of increased national debt.

Yes, Trump did say, “In the last eight years, the past administration put on more new debt than nearly all of the other presidents combined.” But in an hour-long speech, that was the sole reference to the nearly $20 trillion national debt. And the only time Trump used the companion word “deficit” was in relation to trade.

The anti-Reagan

Contrast that scant mention with the Republican philosophy laid down by Ronald Reagan in his first address to Congress in February 1981. Trying to dramatize the horror of $1 trillion in national debt, Reagan memorably said, “A trillion dollars would be a stack of thousand-dollar bills 67 miles high.”

Trump, who reveled in leveraging debt during his business career, does not approach the federal budget like a gimlet-eyed accountant. There will be no lectures from this president about how the government should balance its books like a family should, without borrowing on its credit cards.

While the speech was short on budgetary details, there were broad hints that this will be a shop-’til-you-drop presidency.

Trump promised business a “big, big” tax cut and linked that with a pledge of “massive tax relief for the middle class.” Sounding like any Democrat since the Iraq War went sour, Trump lamented that with the $6 trillion supposedly squandered in the Middle East, “we could have rebuilt our country twice, and maybe three times.”

On health care, Trump’s approach is to throw money at a replacement for what he hyperbolically claimed was “the imploding Obamacare disaster.” Every popular and expensive aspect of health care coverage would be retained in some fashion — from protection for those with pre-existing conditions to expanded Medicaid coverage for struggling families.

Wait, there’s more: Trump trumpeted a budget that “calls for one of the largest increases in national defense spending in American history.” And the president promised “to work with members of both parties to make child care accessible and affordable,” adding, for good measure, a new entitlement for paid family leave for new parents.

Deficits don’t matter

While Trump will never be a detail-obsessed president, even he must understand that this free-spending vision cannot be financed by ending the modest federal subsidies to public television and Big Bird.

Some overnight analyses called the Trump address a return to GOP orthodoxy. In truth, although Trump never said it directly, this was the first major deficits-don’t-matter speech in modern Republican history. Trump’s approach to the budget is that of a man who owned casinos rather than, say, that of a neighborhood dry cleaner struggling to balance the books.

An equally striking change of tone in the Trump speech was its relative lack of fear-mongering about terrorism. A single sentence was devoted to the memories of 9/11, the Boston marathon bombing, and the shootings in San Bernardino. And that passing reference was only designed to justify Trump’s promised revision of his maladroit executive order temporarily banning travel from seven overwhelmingly Muslim countries.

By not overplaying the threat of terrorism, Trump had to fall back on the purported dangers of unchecked immigration and inept trade treaties to explain how a real estate promoter and reality show host became president.

No matter what the immigration statistics are — and no matter how low the overall crime rate — Trump could not abandon his conviction that from over the border “gang members, drug dealers and criminals … threaten our communities and prey on our very innocent citizens.”

A presidential candidacy born in June 2015 with evidence-free claims of “rapists” from Mexico rushing into this country has morphed into a presidency that depends on fears of uneducated and shiftless immigrants taking American jobs. Implicit in Trump’s rhetoric is the idea that if America were a happy place, then a far more orthodox Republican might now be president.

Running for re-election in 1992, George H.W. Bush summarized his strategy for a New Hampshire audience with the awkward line, “Message: I care.” That was Trump’s message, too, as he began his speech with a tribute to Black History Month and a belated expression of concern about the upsurge in bomb threats targeting Jewish institutions and cemetery desecrations.

There was also a message embedded in Tuesday night’s speech for Democrats who gleefully thrill to a caricature version of Donald Trump. And that blunt message is: Never forget how quickly Trump can change his onstage style when the political ratings begin to slip.

Roll Call columnist Walter Shapiro is a veteran of Politics Daily, USA Today, Time, Newsweek and the Washington Post. His book on his con-man great-uncle was just published: “Hustling Hitler: The Jewish Vaudevillian Who Fooled the Fuhrer.” Follow him on Twitter @MrWalterShapiro.