There's no question who North Korea would prefer to see in the White House: incumbent Donald Trump.
His challenger, presidential hopeful Joe Biden, last week called North Korea's young leader Kim Jong-un a "thug" and criticised Mr Trump's handling of the hermit state.
"He's legitimised North Korea, he's talked about his good buddy, who's a thug — a thug — and he talks about how we're better off," Mr Biden said at the final presidential debate.
North Korea isn't too impressed with Mr Biden, either. Last year state news outlet KCNA called him a "rabid dog" — misspelling his name "Baiden" in the process — and said such dogs "must be beaten to death with a stick".
Mr Trump's dealings with the North have been marked by three high-profile meetings, including a photographed encounter in the demilitarised zone (DMZ) that divides North and South Korea, as well as "beautiful letters" from Mr Kim.
But critics say these moves were more show than substance.
Under Mr Kim, the North continues to develop its nuclear arsenal, and just this month it rolled out its biggest ever intercontinental ballistics missile.
South and North Korea are still formally at war, having signed a Cold War-era armistice but not a peace deal, and the US is still widely considered a hostile imperialist threat by Pyongyang.
Mr Trump defended his unorthodox approach to diplomacy in the debate.
"You know what? North Korea, we're not in a war. We have a good relationship. You know, people don't understand having a good relationship with leaders of other countries is a good thing," he said.
Mr Biden hit back: "And we had a good relationship with Hitler before he in fact invaded Europe — the rest of Europe. Come on."
So with hostile words already exchanged, what would a hypothetical Biden presidency mean for North Korea?
Why Kim wants Trump to stay put
Mr Trump was the first US President to meet the now 36-year-old leader, who came to power in 2011.
Mr Kim is the third leader in a communist dynasty that began with his grandfather, Kim Il-sung, in 1948.
Jean Lee, Korea expert at the US-based Wilson Centre, said Mr Trump "was willing to grant Kim legitimacy that no other American president was willing to offer".
"Kim has invested in that unusual relationship and seized the opportunity that President Trump's maverick style of diplomacy has offered," she said.
"They've figured him out now," Anna Fifield, author of The Great Successor: The Secret Rise and Rule of Kim Jong-un, told the ABC.
"And they know that he's unconventional and that he can be manipulated."
Mr Biden, she said, would be a much more "traditional" president, who would expect North Korea to give something up in return for concessions — like concrete progress on denuclearisation.
Robert Kelly, professor of political science at Pusan National University, didn't think a Biden-Kim meeting was on the cards.
"Biden will try to be more clear-eyed and serious, and that means keeping some distance from Kim and generally acting tougher and less sycophantically than Trump," he wrote for National Interest.
When asked at the debate if he would meet Mr Kim under any circumstances, Mr Biden replied: "On the condition that he would agree that he would be drawing down his nuclear capacity. The Korean peninsula should be a nuclear-free zone."
North Korea expert Go Myong-hyun, from the Asan Institute for Policy Studies, said it was clear Mr Biden didn't want to build a rapport with Mr Kim.
"This is problematic for North Korea — it wants to be acknowledged as a nuclear state by the United States and this requires the United States to pay close attention to the Korean peninsula issues," he said.
'Back to the future' with Biden?
Professor Kelly suggested that a Biden presidency could be "back to the future" in terms of US foreign policy on North Korea.
"It's not too hard to predict that Biden will revert to a fairly traditional Washington hawkish approach," he wrote.
While Mr Trump went from a language of fire and fury to love letters and summits, Dr Kelly wrote that he ultimately changed nothing.
He added it was likely Mr Biden will revert, like former presidents Barack Obama and George W Bush, to a "long-running US approach to North Korea: deter, contain, isolate, and sanction".
In her book, Ms Fifield points out the US had seriously considered some unconventional ways to approach North Korea when Mr Kim came to power.
One idea was "basketball diplomacy" due to the young Mr Kim's obsession with the Chicago Bulls — though the Obama administration would later distance itself from a meeting between Mr Kim and former Bulls star Dennis Rodman.
She said a Biden administration would be unlikely to engage in such tactics, and anticipated a return to Obama-era "strategic patience" — where the US essentially ignored North Korea for eight years.
"During that time North Korea wasn't making many waves, so it was pretty easy to ignore them and put them in the too-hard basket," Ms Fifield said.
"Things have changed. North Korea clearly has demonstrated nuclear capacity now.
"But I think that the outside world, the Biden administration, would have so many other things to deal with that it would be convenient for them to leave North Korea on the back burner."
North Korea's nuclear threat
Ms Fifield noted that Mr Kim had got Mr Trump's attention by firing off missiles, but circumstances have changed for North Korea too — the COVID-19 crisis has impacted exports, and movement across the Chinese-North Korean border has also posed problems for Mr Kim.
Mr Kim, who tearfully addressed his people at a parade earlier this month, might be too preoccupied with his domestic situation to provoke the US, she suggested.
But Dr Go from the Asan Institute said if Mr Biden shows indifference towards North Korea, Mr Kim might act out.
"Because provocation is the only leverage that the country has over the United States, it will employ it to force the United States to negotiate on issues that North Korea is interested in," Dr Go said.
A Biden presidency, he added, "is likely to worsen the relations, at least initially".
"The chance of denuclearisation at this point is zero."
Ms Lee, from the Wilson Centre, said Mr Trump's "historic" outreach "has not succeeded in any reduction of the nuclear threat that North Korea poses".
"North Korea has significantly expanded its arsenal during President Trump's four years in office, and even continued to refine its nuclear and ballistic missile technology, even throughout the diplomatic outreach," she said.
"Regardless of who occupies the White House in 2021, Kim will be an even tougher, more emboldened adversary to deal with than he was four years ago."
The women in the wings
It's well in the realm of hypotheticals and speculation, but what about the women flanking Mr Kim and Mr Biden?
Mr Kim's sister, Kim Yo-jong, recently rose to prominence on the world stage, and speculation about her leadership potential reached a fever pitch when her brother was rumoured to be unwell.
"[She] does seem to be being groomed to take over from her brother, but she is very much cut from the same cloth," Ms Fifield said.
There's also been speculation about Mr Biden, who is 77, serving a one-term presidency, and questions about what that would mean for his running mate, Kamala Harris.
Dr Go said Ms Kim and Ms Harris probably wouldn't stray from the paths set out by their male leaders.
"The reason why I expect consistency is because Kim Jong-un himself is executing a strategy that has been handed down to him by his late father, Kim Jong-il," he said.
"Same with Kamala Harris. She's a law-and-order, moderate Democrat — just like Obama. I wouldn't expect much deviation from Biden's foreign policy directions."
Before she became Mr Biden's vice presidential pick and was running to be the Democratic nominee, Ms Harris said she wouldn't be exchanging any Trump-style love letters with the North Korean dictator.
"With all due deference to the fact this is a presidential debate, Donald Trump got punked," she said in November last year.
When asked if she would give any concessions to North Korea, she said no.
"Not at this point. There are no concessions to be made. He has traded a photo-op for nothing."
"He has in every way compromised our ability to have any influence on slowing down, or at least having a check and balance on North Korea's nuclear program."
What about South Korea?
There have been some tense moments between North and South Korea this year.
North Korea blew up a joint liaison building, South Korea charged activists for flying rice and anti-Pyongyang leaflets in balloons over the border, and North Korea shot dead a South Korean defector — prompting a rare apology from Mr Kim.
Mr Trump has been criticised in some circles for suspending war games with South Korea, designed to keep the North in check.
Mr Biden, on the other hand, has said he would continue joint military manoeuvres with South Korea, as he "made clear" on a trip to China back when he was vice president.
"North Korea is a problem. And we're going to continue to do it so we can control them. We're going to make sure we can control them and make sure they cannot hurt us," Mr Biden said in last week's debate.
Under a Biden presidency, regional alliances with South Korea and Japan would be key, Ms Lee said.
"International unity would make it harder for Kim to employ the tactic of sowing division among his neighbours," she said.
"And while the South Korean President, too, has capitalised on the opportunity for spontaneity that President Trump's unpredictability has offered, I suspect that Seoul will breathe a sigh of relief if there is a return to more traditional diplomacy under a potential Biden administration.
"In many ways, President Trump has sidelined President Moon Jae-in; I think the Biden administration would be more conscientious about including South Korea in the negotiations."
But Dr Go said the Moon administration preferred Mr Trump to Mr Biden because the dialogue between Washington and Pyongyang had created space for inter-Korean relations.
"Biden is unlikely to appreciate this point, especially if he actively pursues denuclearisation of North Korea, which contradicts the current South Korean preference for stability over denuclearisation," he said.
"War is unlikely because that's not what North Korea wants — it uses the threat of war to extract concessions, but it doesn't want war because the regime is unlikely to survive one."