SEOUL — June 25 marks 69 years since the start of the Korean War.

In the United States, the conflict is often referred to as "The Forgotten War." But no one ever forgets in North and South Korea, where enduring enmity continues to convulse both countries as well as neighboring nations. Though the war is little remembered in America, 28,000 U.S. troops remain stationed in South Korea to this day.

For decades the military commitment continued because of the threat from North Korea's conventional armed forces. But in recent years, given the North's ballistic missiles and nuclear weapons programs, security on the Korean Peninsula has been even more of a foreign-policy priority for American leaders, including President Donald Trump.

So after leaders of the world's top economic powers wrap up the G-20 Summit in Osaka, Japan, on June 29, Trump will stop in Seoul to continue the dialogue with South Korean President Moon Jae-in. They will "continue their close coordination on efforts to achieve the final, fully verified denuclearization of the Democratic People's Republic of Korea [North Korea]," according to a White House statement. It added that "The two leaders will also discuss ways to strengthen the United States-Republic of Korea [South Korea] alliance and the friendship between our two peoples."

Truth is, denuclearization talks are stalled and the alliance is occasionally strained. But the friendship between the two peoples certainly does remain strong, as I experienced during a recent reporting trip to South Korea that was sponsored by the East-West Center, a nonprofit research and outreach organization devoted to trans-Pacific relations.

In visits to Seoul, South Korea's high-tech business and political capital, to Busan, a bustling industrial port city, to Pyeongtaek, home of the South Korean navy's 2nd Fleet Command, and to Sokcho, where municipal officials still beam over the 2018 "Peace Olympics" in nearby Pyeongchang, Koreans were welcoming and seemed deeply appreciative of America's commitment to their country.

That commitment will likely continue. Despite high-profile summits between Trump and North Korean leader Kim Jong Un, there has been more provocation than progress lately, including recent short-range missile launches by the North.

The North is engaged in "negotiation tactics" because their "hidden intention" is the Pakistan model, said Shin BeomChul, the director of the Center for Security and Unification at the Asan Institute for Policy Studies in Seoul.

Indeed, there's similarity, even symmetry, between Pyongyang's and Islamabad's approach to proliferation, including technical input from A.Q. Khan, the rogue Pakistani scientist who allegedly helped North Korea develop a nuclear weapon.

World powers, including the U.S., pushed back on Pakistan's nuclearization two decades ago, too. But eventually, if reluctantly, they've had to accept the South-Asian nation as a nuclear power.

Pyongyang's nuclearization has again galvanized the international community. But domestic political considerations are key to Kim's commitment to his arsenal even though the weapons development has triggered debilitating sanctions.

This factor gives context to the failure of the Hanoi summit in February, when Trump and Kim met but made no progress on denuclearization. It also explains Kim's furious purge of close associates afterward.

The Trump administration, Shin said, should have had a better understanding of denuclearization before the summit "because it brings great [prestige] to North Korea, not only in foreign relations but with North Korea's inside politics." The meeting alone meant "that our 'Dear Leader' finally showed his greatness because they always told the North Korean people that 'if we develop nuclear weapons things are going to change.' "

Change, albeit in a different direction, is also what the U.S. and South Korea seek. The change they long for would include the North addressing its heinous human-rights record, but denuclearization is the first priority, said Chung-in Moon, a special adviser to President Moon for foreign affairs and national security.

Chung-in Moon (no relation to the president) said that while human rights are a priority, "they can't be imposed" and can only be broached successfully "once you build up trust with the North."

Trust is at times a challenge between Seoul and Washington, and more often between Seoul and Tokyo due to ongoing controversies over wartime "history issues" such as the Korean "comfort women" and forced laborers Japan exploited during World War II.

But then again, there are strains in the relationship between China and North Korea, as well. "Pyongyang's fear of Beijing is far greater than their animosity of the United States," Moon said.

And yet, Chinese President Xi Jinping visited Kim in Pyongyang last week, displaying respect before meeting with Trump at the G-20 Summit. And after a previous Xi-Kim confab in Beijing, the state press revived a rhetorical description of their nations' relationship as being like that between "lips and teeth."

China's teeth were bared toward South Korea, in the form of economic punishment, after the South agreed to deploy America's THAAD antimissile battery in response to the threat from the North.

That threat, however, is not idle. Scores of incursions have taken place since the war ended in 1953 — without a peace treaty. Among the more recent attacks were the 2010 shelling of Yeonpyeong Island that killed four, and an apparent torpedo attack on the South Korean warship, ROKS Cheonan, which killed 46.

The ship's wreckage is on display in a memorial hall in Pyeongtaek, home of the ROK Navy 2nd Fleet Command, where Lieutenant Junior Grade Kang Hawon led a tour, and a moment of silent prayer for the victims, as he earnestly explained the attack on the ship and the nation, and dismissed any notion of a passive North.

There's also some solemnity at the Demilitarized Zone separating the two Koreas, including ribbons with wishes for peace and reunification tied to a fence topped with barbed wire.

And in the glistening Dorasan train station, just 700 meters from the southern DMZ border, there's a sign for the train to Pyongyang that reflects a patient, plaintive wait for a breakthrough that never seems to arrive.

Those totems of the enduring division were to be expected. What wasn't predictable were the amusement-park rides, Popeyes chicken franchise and busloads of cheerful Chinese tourists checking out the South's accessible, commercial side of the DMZ.

The visitors couldn't get close to the DMZ's emblematic scene of North and South Korean soldiers glaring at each other. But visitors smilingly posed with uniformed mannequins of stalwart South Korean soldiers at the Third Tunnel tourist site, which allows visitors to descend into one of the four tunnels the North dug for an ostensible stealth attack on the South.

These tourist tropes (and traps) are jarring, especially compared to a binocular peer into the North showing a starker landscape and a Potemkin village built for propaganda purposes. But the scene speaks to the incredible, perhaps irresistible, pull of commerce, if not capitalism, for a North falling ever further behind the South — and the world.

Many in South Korea hope the pull will prevail — for the sake of peace, to be sure, but also to reconnect South Korea, which despite being linked by land to the continent of Asia has existed as a de facto island nation ever since Korea's political division. Normalization would open access to rail routes throughout Asia and Europe.

Yoo Jae-soo, Busan's vice mayor for economic affairs, certainly hopes Kim hears and heeds the call for unity, especially since his city, with access to three seas, is already a major shipping hub and would be even more ideally located if North Korea begins to engage with the world's economy.

Yoo, a former World Bank official, has long observed how trade can connect economies and, more profoundly, people. He said the most positive result of the U.S.-South Korea Free-Trade Agreement wasn't commerce, but "a reaffirmation of the strong alliance."

Such links are critical in a region buffeted by Beijing's territorial aggression and Pyongyang's proliferation. Which is just one more proof that Trump's scuttling of the Trans-Pacific Partnership (TPP) pact between the U.S. and 11 other Pacific nations was a major geostrategic error (Hillary Clinton, his 2016 opponent, opposed it wrongly, too).

Last October Yoo traveled to North Korea to discuss opportunities should an opening occur. He left unimpressed with the "terrible" infrastructure but hopeful about the economic and political possibilities.

"My impression is that even though it is an uphill battle and bumpy road to finally open up North Korea, [the momentum] is not reversible," Yoo said.

And yet, in a vivid display of the vicissitudes of Pyongyang's opaque politics, the key North Korean official Yoo met — Kim Yong-chol — was the subject of intense speculation just days after our interview when a South Korean newspaper reported that he had been sentenced to hard labor after the failure of the Hanoi summit (he later surfaced with Kim Jong Un, but appears to have been downgraded).

The hope of some eventual thaw was still afloat at the Busan Port Authority, where officials detailed extensive expansion plans for what is already the world's second-leading transshipment port.

A harbor tour on the Sae Nuri Ho ferry showed the extraordinary scale of the existing operation. But the earnest officials pointing to maps were no match for the glee of a group of touring students who crowded the lower deck. Amid massive cranes and container ships they couldn't contain themselves, laughing and taking selfies like kids everywhere.

Kids everywhere, however, is not always the norm in today's South Korea, which has among the lowest birthrates of any country, concerning many about the trajectory of the economy, and more profoundly, the nation.

The youth on the ferry represented yet another generation coming of age in a nation increasingly tied to the world but estranged from fellow Koreans, held hostage by the North Korea's dynastic dictatorship.

At times, generations in the South seem divided on reunification. "There are some concerns about it because there might be some economic shock due to reunification," Lee Joo-ah, editor-in-chief of the EWHA Womans University newspaper, said. "There is a very big difference between generations because younger people are mostly positive about it but older generations, they think negatively on reunification because they have bad memories about the Korean War."

This may in fact be true for some elderly Koreans. But some seared by the war, like Kim Ick Sun, born in what is now the North in 1935, remembers his youth ripped asunder by the violence and depravity of the war that's left him in the South ever since.

With a clear memory, he recounted his harrowing experience of losing loved ones and his place in the world. With a clear grasp of the challenges, he ended his life's story with his hopes for one Korea.

"Reunification is not a simple thing," Kim said. "Kim Jong Un will not give up his power because he has to protect the Kim family's kingdom. I think this is a tragedy of the Korean people."

Wary yet wistful, Lee concluded by saying, "I am looking for that day, and we have to make an effort so unification is possible. So I remain hopeful."

Kim Ick Sun, like most Koreans, never enjoyed the luxury of the Korean War being "forgotten."

Maybe, someday, the schoolkids on the Sae Nuri Ho ferry will.

John Rash is a Star Tribune editorial writer and columnist. He is at john.rash@startribune.com.