Republican presidential candidate Donald Trump holds up his book “The Art of the Deal,” given to him by a fan as he speaks during a campaign stop Nov. 21, 2015, in Birmingham, Ala. (Eric Schultz/AP)

The central premise of Donald Trump’s presidential candidacy was that he was a dealmaker. He wrote that book. He had that TV show. He built a real estate empire on the sheer force of wile and handshakes (or so he would present it).

The result? A president who had gotten more done than any before him, as he himself would present it on Twitter and in speeches. Signing tons of legislation. Taking a number of other actions. Promises made, the signs at his campaign rallies read — and promises delivered.

Each of those assertions is contestable if not demonstrably false. But the link between the presidency he promised and the presidency he delivered is of new importance, given the surprise announcement Thursday evening that Trump planned to meet with North Korean leader Kim Jong Un at some point over the next few months. The Trump, who in 1984 told this newspaper that he could be the nation’s most effective negotiator to scale back nuclear tensions with the Soviet Union, now has the opportunity to potentially defuse the most unstable nuclear situation in the world. It’s the moment that he’s been awaiting for a quarter of a century.

Put another way, he has the chance to put his money where his mouth is. Just as, when he was inaugurated last year, he was given the chance to fulfill his campaign’s description of how he would lead.

There’s just one problem. As president, he hasn’t really closed many deals.

He started making deals even before he took office. There was his complaint in December of 2016 that the government signed new contracts with Boeing to replace Air Force One that had ballooned to more than $4 billion. He met with Boeing executives before taking office (and his inaugural committee accepted a sizable donation from the company) and in February 2017 announced that he had knocked $1 billion off the $4.2 billion price tag. Last month, that deal was revised a bit: The final cost would be $3.9 billion.

His most famous pre-inauguration deal, though, was to keep jobs at a Carrier plant in Indiana. Shortly before Christmas 2016, he announced that a plant in the state wouldn’t close, thanks to a deal worked out with the help of Indiana’s then-governor, Mike Pence. The plant remains open, but in January another 200 factory workers were laid off.

Then he was inaugurated.

Trump learned pretty quickly that the power of the presidency has a lot of constraints that being a chief executive doesn’t. More power — but less ability to act unilaterally.

Trump’s frequent assertion that he had done more than any modern president (which, again, is not true according to most observers) was based on two bits of data (to the extent that it was based on data).

The first was the number of bills he had signed, which by the end of his first year was lower than any other elected president’s first year in the modern era.

Those new bills were not deals he cut. Most were either symbolic or passed solely on the strength of the Republican majority. Trump promised sweeping deals to fund infrastructure, cut taxes and replace Obamacare. There was never any legislation dealing with infrastructure on the table. The tax bill passed the Senate on a party-line vote. Efforts at a comprehensive Obamacare replacement fumbled their way through 2017 and never matched what Trump had promised on the campaign trail, eventually stalling in the Senate when several Republicans balked.

One could argue that Trump made deals within his own party to pass the tax bill, given the pressure he put on the House Freedom Caucus to get on board. That plays down two things, however. The first is that much of the arm-twisting and cajoling was a function of Republican leaders on Capitol Hill (though they were savvy enough to heap praise on Trump when the cameras were on). The second is that he couldn’t get the job done when it came to the party’s health-care bill.

One bill that was a function of a deal was when Trump bucked his party to agree with Democratic leaders on a path forward on lifting the debt ceiling in September. That deal, though, didn’t extract much (if anything) from his political opponents. While he has publicly toyed with bipartisan deals on other things — how to handle immigrants brought into the United States illegally as children, for example, or gun violence — no actual deals have emerged. At one point, in fact, he pledged to agree to any compromise deal on those enrolled in the Deferred Action for Childhood Arrivals program, but when presented with a bipartisan agreement on immigration last January, he rejected it.

The other metric Trump cites as a marker of his success is the number of executive orders he’s signed to reverse past federal regulations or shift the focus of the executive branch. Those orders, of course, are by definition unilateral and not in any sense “deals.”

That includes his most significant action on trade, the imposition this week of tariffs on aluminum and steel imports from some countries. Trump’s tariffs were announced the same day that 11 other nations signed the Trans-Pacific Partnership that was abandoned by the United States shortly after his inauguration.

Trade deals were supposed to be Trump’s bread and butter. The United States, Canada and Mexico are negotiating how to overhaul NAFTA, without success. In November, the administration announced new trade deals with China meant to reduce the trade gap. Many were specific deals (or even just memorandums of understanding) between Chinese and American companies.

He has also taken credit for proposed efforts to bring manufacturing back to the United States. Some of those proposals predated his presidency. In at least one notable example, a plan to open a Foxconn facility in Wisconsin, The Washington Post’s fact-checkers determined that Trump’s effort to claim credit was undue.

Other international deals have been similarly spotty. Shortly after taking office, he got into a heated argument with the prime minister of Australia about a plan to send refugees to the United States. Trump called it the “worst deal ever,” but they began arriving in September. His efforts to pressure NATO members to pay more on defense — a long-standing American frustration with the body — has led to an increase in spending, though less than Trump sought.

Trump has been successful at efforts to free Americans held overseas. Shortly after taking office, he intervened with the Egyptian government to get charity worker Aya Hijazi freed from captivity. He also got Otto Warmbier freed from North Korea, though Warmbier died shortly after his return. Trump also took credit for getting three UCLA basketball players released from custody in China after they were arrested for shoplifting. One of the players’ parents, LaVar Ball, denied that Trump played much of a role, kicking off a social-media feud. (A report from ESPN last week supported Ball’s claim that the situation was resolved before Trump weighed in.)

In July, Trump announced another international deal: A new cease-fire agreement in Syria. While other cease-fire efforts in the country’s civil war had failed, the deal announced by Trump seemed more significant in part because it was reached during a conversation with Russian President Vladimir Putin and involved that country’s significant investment.

That deal was one of Trump’s most successful. The cease-fire, covering three provinces in the southwestern region of the country, has largely held since.