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As Kim wooed Trump with ‘love letters,’ he kept building his nuclear capability, intelligence shows

In this photo provided by the North Korean government, North Korean leader Kim Jong Un and President Trump greet one another on June 30, 2019, over the military demarcation line at the border village of Panmunjom in the Demilitarized Zone. (Korean Central News Agency/Korea News Service/AP)

In a secret letter to President Trump in December 2018, North Korean leader Kim Jong Un likened the two leaders’ budding friendship to a Hollywood romance. Future meetings with “Your Excellency,” Kim wrote to Trump, would be “reminiscent of a scene from a fantasy film.”

Yet even as he penned the words, Kim was busy creating an illusion of a different kind. At six of the country’s missile bases, trucks hauled rock from underground construction sites as workers dug a maze of new tunnels and bunkers, allowing North Korea to move weapons around like peas in a shell game. Southeast of the capital, meanwhile, new buildings sprouted across an industrial complex that was processing uranium for as many as 15 new bombs, according to current and former U.S. and South Korean officials, as well as a report by a United Nations panel of experts.

The new work reflects a continuation of a pattern observed by analysts since the first summit between Trump and Kim in 2018. While North Korea has refrained from carrying out provocative tests of its most advanced weapon systems, it never stopped working on them, U.S. intelligence officials said. Indeed, new evidence suggests that Kim took advantage of the lull by improving his ability to hide his most powerful weapons and shield them from future attacks.

President Trump on Aug. 9 said he thought he would meet again with North Korean leader Kim Jong Un. (Video: The Washington Post, Photo: Jabin Botsford/The Washington Post)

The pause in testing has produced benefits for both leaders, despite the lack of tangible progress toward the stated goal of the United States in any accord: a denuclearization of the Korean Peninsula in exchange for ending crippling economic sanctions against the North. Kim’s show of restraint has allowed Trump to claim a partial foreign policy success, even as administration officials acknowledge that North Korea has not eliminated a single bomb or dismantled any of its missile factories.

Trump’s North Korean gamble fails to pay off

For Kim’s part, the easing of tensions has opened new routes for circumventing sanctions while his factories quietly churn out more nuclear warheads and bigger missiles to carry them, current and former U.S. intelligence analysts and nuclear experts say.

“North Korea hasn’t stopped building nuclear weapons or ­developing missile systems; they’ve just stopped displaying them,” said Jeffrey Lewis, director of the East Asia Nonproliferation Program at the Center for ­Nonproliferation Studies in Monterey, Calif. “They stopped doing the things that made bad news cycles for Trump.”

On Aug. 23, President Trump said that North Korean leader Kim Jong Un has been “pretty straight” with him, despite two short-range ballistic missiles tests. (Video: The Washington Post)

The result, two years after the start of Trump’s unconventional peace overture, is a North Korea that U.S. officials say is better armed, with a growing nuclear arsenal scattered across a network of bunkers newly hardened against a potential U.S. airstrike. Kim, meanwhile, has gained an advantage that has eluded other North Korean leaders: a personal friendship with a U.S. president — one in which Trump describes Kim admiringly and shows off what he has called “love letters” exchanged between the two leaders. The contents of dozens of letters were revealed last month by journalist Bob Woodward in his book “Rage.

Some experts see signs that Kim is losing patience with diplomacy and may be preparing to revert to more-aggressive behavior, including possible tests or displays of new weapons. But many analysts believe that such provocations are not likely to occur until after Nov. 3, because of Kim’s apparent wish to avoid undermining Trump’s reelection chances.

“In theory, an ‘October surprise’ — some form of provocation — could be in play, but this is not a normal election year,” Sue Mi Terry, a former senior analyst on North Korea for the CIA, said at a North Korea policy forum last week. “From Kim Jong Un’s perspective, he still prefers to deal with Trump.”

Token gestures

By any objective measure, the risk of imminent hostilities with North Korea has receded since Trump’s controversial decision to pursue personal diplomacy with Kim. In the early months of the Trump presidency, North Korea conducted its sixth nuclear test, detonating a powerful new weapon believed by experts to be a hydrogen bomb. It also successfully launched two new types of intercontinental ballistic missiles, one of which was judged capable of reaching cities on the U.S. East Coast.

Diplomacy between Washington and Pyongyang, meanwhile, devolved into name-calling. Trump publicly derided the North Korean leader as “Rocket Man,” while the U.S. president was mocked in official North Korean communiques as a “dotard.” In recorded interviews for Woodward’s book, Trump acknowledged that the two countries narrowly avoided war in 2017, inching closer to the edge than Americans knew at the time.

Woodward: Trump says U.S. came close to war with North Korea in 2017

Trump’s announcement that he would meet unconditionally with a North Korean leader — something previous presidents, Republican and Democrat, had declined to do — was greeted skeptically by many arms control experts. It was clear that the highly theatrical 2018 Singapore summit was mostly symbolic, as the talks failed to produce a substantive agreement, or even a shared understanding of what a “denuclearization” of the Korean Peninsula actually meant.

Still, many critics of the summit would later credit Trump’s team for its willingness to try something different.

“We had never tested whether the negotiation hypothesis — the idea that talking to the leader directly about denuclearization — could work,” said Victor Cha, director of Asian affairs at the White House National Security Council during the George W. Bush administration and currently the Korea chair at the Center for Strategic and International Studies. “We had never tried that.”

Even though disarmament talks quickly stalled, the lessening of tensions was a significant and undeniable achievement. The “strategic patience” doctrine adopted by the Obama administration over the previous eight years had proved unsuccessful in slowing North Korea’s pursuit of nuclear weapons and advanced missiles, noted John Delury, a professor at Yonsei University in Seoul.

“The logic behind engaging Kim Jong Un was sound and remains sound,” Delury said. “Trump was able to get certain things done.”

Yet despite two additional summits the following year, talks on eliminating North Korea’s nuclear arsenal produced little more than token gestures. Trump basked in the media spotlight when he crossed the Korean demilitarized zone to shake hands with Kim, but the author of “The Art of the Deal” could not persuade Kim to open his weapon bunkers for inspection, or to part with his nuclear weapons, estimated by U.S. intelligence officials at between 40 and 60. Those officials concluded that Kim never intended to give up his arsenal, which the dictator views as the ultimate guarantor of his regime’s survival.

“There was the willingness to engage at the high level, but then it kind of crumbled from there,” Delury said. “Trump’s chaotic and distracted theatrics of politics meant that it didn’t really create a lasting process.”

Miniature nuclear devices

Still, more than a year after the last summit, North Korea’s unilateral freeze on nuclear and ICBM testing remains intact. So does, apparently, the two leaders’ mutual admiration. Trump has told followers at political rallies that he and Kim “fell in love” after their first meeting. Kim’s letters to Trump, as quoted by Woodward in his book, are fawning paeans rendered in language that would make a romantic novelist blush.

“I cannot forget that moment of history when I firmly held Your Excellency’s hand,” Kim wrote in a Dec. 25, 2018, missive. Trump’s reply, three days later: “The only two leaders who can do it are you and me.”

But all along, North Korea — a serial cheater on past nuclear agreements — was hedging its bets. Multiple strands of intelligence collected by U.S., South Korean and Japanese intelligence agencies have confirmed that Kim never missed a step in his march toward creating a credible nuclear deterrent that included powerful warheads and a variety of advanced missiles for delivering them.

Officials: North Korea concealing key aspects of its weapons program

Exactly how many new bombs North Korea has built since the Singapore summit is not publicly known, but analysts calculate that the country’s nuclear weapons complex currently generates enough fissile material for up to seven new bombs each year — meaning that Kim’s nuclear stockpile has possibly expanded by about 15 warheads since the two leaders first met.

North Korea’s recent progress on weapon systems is detailed in a report by a U.N.-appointed Panel of Experts that compiles intelligence on North Korea supplied by multiple countries, including the United States and South Korea. A pre-publication draft of the report, obtained by The Washington Post, concludes that North Korea has continued to manufacture nuclear bombs, including more “miniature nuclear devices to fit into the warheads of its ballistic missiles.” Two U.S. officials familiar with the findings said the report's conclusions are broadly shared by U.S. intelligence agencies.

The report highlights a construction boom at six military bases where North Korea manufactures and tests components for new missiles, describing a “level of activity [that] is constant.” Particularly striking, the report said, is a surge in subterranean building projects, including new bunkers and tunnels that have been dug beneath existing bunkers and storage facilities, the report said.

“An effort is made at some sites to enhance the undetectability and the camouflage of the existing or recently built infrastructures,” the report said.

The U.N. experts also noted the appearance of new or expanded facilities at North Korea’s uranium-processing plants, including a large industrial complex at Pyongsan that refines uranium ore. The improvements could enable Pyongyang to build more nuclear weapons faster.

In addition, the report cited evidence of preparations for a possible future resumption of tests. Advance work appeared to be underway for a possible missile test at a navy base in Sinpo, a port city on North Korea’s northeast coast and the site of previous tests of submarine-launched ballistic missiles.

Meanwhile, an elaborate North Korean network for smuggling weapon parts continues to operate. According to a separate analysis by South Korean researchers last month, Kim’s government successfully imported at least $30 million worth of banned missile components just in 2018, the year when the ICBM testing freeze went into effect.

“Even amid the flurry of diplomacy in 2018,” said report author Jina Kim of the Korea Institute for Defense Analyses, a think tank affiliated with South Korea’s Defense Ministry, “North Korea never stopped developing military options as a backup.”

Forcing a disarmament deal

Trump administration officials say they are fully aware of Kim’s continued pursuit of nuclear weapons, but they argue that a combination of diplomacy and continued economic pressure will eventually compel North Korea to give up its nuclear arsenal. Some analysts believe that North Korea is waiting out the U.S. presidential election, and that Kim may be willing to strike a bargain after Nov. 3, depending on the outcome.

Harsh U.S. and U.N. economic sanctions have battered North Korea’s economy. Yet pressure from sanctions has slowly ebbed, in a side effect of the Kim-Trump summits. As tensions in the region eased, both China and Russia curtailed enforcement of the restrictions, allowing North Korea to export more of its coal to foreign markets while bringing in critical supplies of gas and oil.

How Russia quietly undercuts sanctions on North Korean coal

North Korea’s economy remains under severe strain, however, because of problems unrelated to the nuclear weapons crisis. After the start of the coronavirus pandemic, Kim closed the border with China, sealing off commerce with the country’s main trading partner. Numerous cities and farming provinces also suffered massive damage because of historic flooding over the summer.

Some experts believe the extreme financial stress could eventually force Kim to agree to a disarmament deal. But others note that North Korean leaders have withstood similar pressures in the past, at times even allowing their citizens to endure starvation in order to procure the weapons they believe will help them stay in power.

In the meantime, analysts say, neither Kim nor Trump is likely to jeopardize their personal relationship. The odd friendship has continued to offer value — a temporary lessening of tensions and a chance to stand together in the international spotlight as statesmen — even as prospects for a nuclear-free North Korea appear to recede further from sight.

“There have been a lot of efforts, but in substance, I see no progress at all,” said Chun Yung-woo, a former South Korea national security adviser who participated in nuclear talks with North Korea in the mid-2000s.

“North Korea is more dangerous. It has more nuclear warheads, or fissile materials with which to produce nuclear weapons,” Chun said. “In that regard, at least, North Korea has more capability to destroy peace on the Korean Peninsula. I wouldn’t describe that as any progress.”

Denyer reported from Tokyo. Min Joo Kim in Seoul contributed to this report.