Ivanka Trump called the walk to the other side of one of the world's most fortified borders "surreal."

Few Americans alive today have set foot inside North Korea, the isolated, nuclear-armed dictatorship sometimes called the Hermit Kingdom.

On Sunday, Ivanka Trump became one of them, capping a consequential three-day Asian trip in which the president's eldest daughter played a very public role that blended family ties with diplomatic work that is usually performed by diplomats.

She pronounced the short walk to the other side of one of the world's most fortified borders "surreal."

Previously, at the Group of 20 economic summit in Japan, Ivanka Trump was everywhere - at her father's side at times when other leaders' spouses were present (first lady Melania Trump skipped the trip), in meetings during which her presence puzzled other participants, and even giving an awkward video "readout" of Trump's meeting with Prime Minister Narendra Modi.

A video of Ivanka Trump talking with British Prime Minister Theresa May, French President Emmanuel Macron, Canadian Prime Minister Justin Trudeau and International Monetary Fund chief Christine Lagarde at the G-20 also went viral over the weekend. Lagarde's impatient side-eye as Ivanka Trump interjects in what appears to have been a back-and-forth between Macron and May suggested irritation at finding herself standing alongside the daughter of the U.S. president - rather than the president himself.

"As soon as you charge them with that economic aspect of it, a lot of people start listening who otherwise wouldn't listen," May can be heard saying, as Lagarde nods in agreement.

"And the same with the defense side of it, in terms of the whole business that's been, sort of, male-dominated," Ivanka Trump then says, as a startled-looking Lagarde turns toward her, then purses her lips.

The first daughter's prominence in Japan and South Korea appeared to be by design - a sign of her influence with President Donald Trump and the absence of influential opponents within the administration.

It's not clear, however, to what end.

Ivanka Trump shuttered her clothing business after joining the administration, although not right away, and has largely stepped away from her old life as an entrepreneur and social mainstay in New York. She and her husband, senior White House adviser Jared Kushner, let it be known last year that they would remain in Washington and in the White House indefinitely.

Her ambitions are unknown - she demurs on any desire for public office. Over time, her work on women's issues and entrepreneurship has increasingly resembled that of a State Department envoy. She made a lengthy trip to India in November 2017, and several others since, sometimes with her father and sometimes on her own. On a solo Africa trip in April, Trump said she would campaign for a proposal to allow women to own and inherit land in Africa and promote a $50 million U.S. development project in Ethiopia.

The gray area she occupies - family, employee, envoy, advocate - frequently overlaps with the work of career diplomats. But her unfamiliarity with some elements of diplomacy were on display on this trip, including when she pronounced India a "critical ally." It is a partner in many areas, but U.S. diplomats avoid the higher terminology of ally.

Mostly, her prominence on a major foreign trip sends a message about whom other countries should listen to or court, said Christopher Hill, a former U.S. ambassador to South Korea and other nations.

"It looks to the rest of the world like we have a kind of a constitutional monarchy," said Hill, who oversaw nuclear talks with North Korea at the close of the George W. Bush administration.

"It's increasingly problematic in terms of our credibility," Hill said. "It says to our allies, to everyone we do business with, that the only people who matter are Trump and his family members."

Ivanka Trump had front-row seats at nearly every televised session in Japan and for President Trump's visit to South Korea, where the trip to the demilitarized zone was the main event. She and Kushner were among the small U.S. delegation at the border, which included Secretary of State Mike Pompeo but not White House national security adviser John Bolton, a longtime skeptic of diplomacy with North Korea. Bolton instead had left to fly to Mongolia.

Ivanka Trump worked the room at a meeting of South Korean business leaders on Saturday, with cameras catching the smiling interactions. Secretary of State Mike Pompeo did not attend. She remained in the front row at Trump's news conference in Seoul, nodding in agreement as the president spoke, after Pompeo ducked out minutes into the event.

Along the way were opportunities for the kind of "branding" Ivanka Trump espouses as a tool for empowering women - a main theme of her work as presidential adviser, some of it captured on her Instagram account.

A video shows Ivanka Trump looking into the camera as she recounts meetings with German Chancellor Angela Merkel, PM Modi and others at the G-20, and touts a program launched by G-20 members to expand access to capital for women in the developing world.

"It's been a great success, one of the truly great deliverables of the G-20 in Hamburg" two years ago, Ivanka Trump says. "Very excited to talk about the deliverables of this important initiative."

She also posted a photo in which she and Kushner pose with Trump and Japanese Prime Minister Shinzo Abe.

"Today, President Trump held dynamic and productive meetings with many world leaders to discuss key security and economic issues," she wrote. "It is an honor to be a member of the U.S. delegation during an incredible first day of the #G20OsakaSummit."

But the final day of Trump's trip - with the history-making visit to the DMZ and an address to U.S. forces stationed in South Korea that had at times sounded like a campaign rally - produced the most dramatic images of Ivanka Trump in her hybrid and often inscrutable role.

Trump invited Pompeo onstage at the Osan Air Base, and gave a nod to traditional diplomacy by saying that a "whole team" would follow up on Trump's third face-to-face discussion with North Korean leader Kim Jong-Un.

Pompeo trotted onto the stage and started toward Trump but hadn't made it to the lectern when Trump moved on to the big reveal.

"And you know who else I have?" he asked, leaning toward the crowd for dramatic effect.

"Has anybody ever heard of Ivanka? he asked, to whoops from the crowd.

"Come up here," he commanded, as Ivanka Trump appeared at the rear of the stage.

"She's going to steal the show," Trump said, grinning.

As Pompeo fell in beside Ivanka Trump and the two walked toward him, President Trump quipped, "What a beautiful couple," and the audience howled. "Mike! Beauty and the beast," Trump went on, as he also acknowledged Harry Harris, the U.S. ambassador to South Korea.

Pompeo appeared to gesture to Ivanka Trump to go first, but she stepped aside and signaled for him to speak. After Pompeo briefly thanked the troops, there was a roar as Ivanka Trump stepped forward. President Trump and Pompeo flanked her, grinning, as she also thanked the troops and their spouses and families.

"They made the trip with me, and we spent a lot of time, a lot of time," Trump said.

Ivanka Trump's presence at the DMZ is particularly troubling, said Jenny Town, a North Korea specialist at the Stimson Center and editor of 38 North, a publication focused on North Korea.

"It was not appropriate for Trump to bring his kids to this meeting," Town said. "But it was a weird mix of people on the U.S. side to begin with. What's notable, however, is who wasn't there: Bolton."

Trump has sidelined or fired some professional national security advisers and undercut others, including at times Pompeo and Bolton. He has never publicly criticized or contradicted Ivanka Trump or Jared Kushner, although he has jokingly teased Kushner at times.

Pompeo spoke to reporters after the DMZ visit and outlined some of the bureaucratic next steps with North Korea.

Pompeo was asked whether his presence at the DMZ was a signal to North Korea, which has complained about him and reportedly sought to go around him with Trump. Pompeo, who has a close relationship with Trump, did not mention Ivanka Trump in his answer, though her presence Sunday had served to underscore the personal nature of Trump's direct diplomacy with Kim.

"So far as I know, President Trump has always had me in charge" of negotiations, Pompeo said.