By Hyonhee Shin
SEOUL (Reuters) - North Korea's Kim Jong Un awaits the winner of next week's U.S. presidential election armed with greater leverage in high-stakes nuclear diplomacy, thanks to a more powerful and versatile arsenal of weapons than at the start of the Trump presidency.
While Donald Trump boasts of having prevented war and exchanged "beautiful letters" with Kim, the U.S. president has not wrested a single significant commitment from the North to roll back its weapons of mass destruction programme, according to Seoul officials and analysts.
For Kim, Joe Biden poses a more challenging negotiating partner, more likely to pen a "Dear Jong" letter than engage with him in person - even though the bar for summit diplomacy is lower due to the precedent set by Trump, the officials say.
Pyongyang embarked on an unprecedented series https://www.reuters.com/news/picture/key-events-in-north-korea-us-ties-during-idUSRTX85VOS of weapons tests in 2017, declaring itself a nuclear power after undertaking its biggest nuclear blast and longest-range intercontinental ballistic missile (ICBM) launches.
After months of tightening sanctions and trading threats, Trump then became the first sitting U.S. president to meet with a North Korean leader at a summit in Singapore in 2018.
"Kim Jong Un has been doing what he needs to stay in power, and nuclear weapons are the most powerful means of survival," a South Korean official who is familiar with the diplomacy said, asking not to be named because of the sensitivity of the issue.
The official called it a "Trump effect" that Biden did not rule out a summit with Kim, even as the Democratic challenger called the North Korean leader a "thug" and said a meeting is possible only if Pyongyang rolls back its nuclear capability.
"Whoever wins the election, he has to solve the question of how to derive substantive denuclearisation under an agreed roadmap that clarifies an end state of the programmes," another Seoul official said.
Although the North has largely kept to a moratorium on nuclear and long-range missile tests, it has continued to develop new missiles, as well as engines potentially designed for ICBMs and new mobile launchers, while building its nuclear weapons-grade stockpile, experts say.
While the United States' far greater military might could swiftly inflict critical damage on North Korea, Pyongyang now poses a threat with its nuclear missiles capable of striking the U.S. mainland.
Expert assessment of the North's new multiple rocket launchers and surface-to-surface missiles also rate them highly effective in any conflict on the peninsula.
Days after Kim's third meeting with Trump last year, the North offered a glimpse of a large submarine, believed to be capable of carrying multiple submarine-launched ballistic missiles (SLBM). It was seen by military experts as another game changer, just as the Hwasong-15 ICBM launch in 2017 was.
A military parade https://www.reuters.com/video/?videoId=OVCZJVWBV&jwsource=em this month highlighted how the North has beefed up its strategic weapons. It featured a new SLBM and a previously unseen ICBM designed to carry multiple warheads - dubbed by experts as a "monster" and rolled out on an 11-axle transporter.
The display was intended to show Kim could take up negotiations where he had left off with Trump, or return to confrontation by resuming advanced weapons tests, said Lee Soo-seok, a senior fellow at the Institute for National Security Strategy.
"Nuclear development isn't something they can stop doing but if there was some kind of a deal, they might have adjusted its pace and gone more low-key, instead of showcasing the ICBM," Lee said. "Trump might now be regretting not giving whatever half-baked deal and being unable to sell it as his legacy."
Even as the coronavirus pandemic, border closure with China and recent typhoons add pressure to an economy already pummelled by international sanctions, Kim has dug in for a long battle.
He has let unofficial markets thrive, allowing some breathing room for ordinary people to trade goods and securing funding sources for his pet projects.
The young leader made rare, tearful confessions that he failed to tackle economic hardships in a speech at the recent military parade, but said "time is on our side."
"The longer negotiations drag on, the greater North Korea's nuclear and missile capabilities grow, but Washington might think they hold the key through sanctions," said Koh Yu-hwan, president of the state-run Korea Institute for National Unification in Seoul.
"Now stakes are higher for both sides, and the game would depend on who can hold out better in the face of threats they pose to each other."
(Reporting by Hyonhee Shin; Additional reporting by Sangmi Cha; Editing by Jack Kim and Lincoln Feast.)