SEOUL - Lee Juhyun contributed to this report.
Talks with North Korea are stalled yet again. Pyongyang has ramped up its ballistic missile launches. And in the United States, the leading contender to challenge President Donald Trump is threatening a tougher approach toward Kim Jong Un.
Add it all up, and these are increasingly challenging times for the liberal government of South Korean President Moon Jae-in, which against all odds helped bring about the U.S.-North Korea nuclear talks in 2018, but can now do little to help move them forward.
"The problem should be dealt with by the end of the year," Song Young-gil, a South Korean lawmaker and member of President Moon's Democratic Party, told VOA. "Mr. Trump may say timing doesn't matter, but there isn't enough time."
North Korea has set an end-of-year deadline for the U.S. to change its approach to the talks, which have been stalled since a Trump-Kim summit in February broke down over how to pair sanctions relief with steps to dismantle North Korea's nuclear program.
Kim has agreed to restart talks after U.S.-South Korea military drills end later this month, according to Trump. But neither side has publicly softened their stance. And it's not clear what a fourth Trump-Kim meeting could accomplish, if not accompanied by more substantive working-level negotiations.
"(Trump and Kim) have already had three summits. It's not like they can call on the Pope or God to help them now. There is no final card for them to play," says Song, a member of the National Assembly's Foreign Affairs and Unification Committee.
Putting the U.S.-North Korea talks back on track is a top priority for Moon, who is in power until 2022. But with a U.S. presidential election just over a year away, Moon may soon find himself with a partner in Washington that is less supportive of talking with Pyongyang.
Tougher US approach coming?
Joe Biden, the Democratic presidential frontrunner, has vowed to roll back major parts of Trump's outreach to North Korea.
As vice president, Biden helped oversee former President Barack Obama's policy of "strategic patience," which relied on diplomatic isolation, economic sanctions, and military pressure in an attempt to convince North Korea to give up its nuclear weapons.
Biden now says he would keep up the pressure.
"I'd make it real clear: look, you want to talk, you want to deal with us, you want sanctions lifted, show me something ahead of time," Biden told CNN last month.
In recent months, Biden has referred to Kim as a "dictator," a "thug," and a "murderous tyrant." North Korean state media returned the favor, calling Biden an "imbecile" and a "fool of low IQ."
Despite the animosity, some in South Korea's government expect talks with North Korea to continue, no matter who wins the U.S. election. One reason: changing geopolitical circumstances.
In the view of one senior South Korean Blue House official who spoke to VOA on condition of anonymity, a return to Obama's policy of "strategic patience" is unlikely, in large part because the fundamental calculation has changed: it is now undeniable North Korea possesses nuclear weapons.
"Strategic patience -- what would we be waiting for?" asked the South Korean official.
But although Obama failed to eliminate North Korea's nuclear threat, Trump's approach seems to be faring little better. Despite his summits with Kim, Trump has not convinced North Korea to begin giving up its nuclear weapons.
Some in South Korea's government insist the deadlock could be broken if both sides showed more flexibility. They favor an incremental approach in which Washington and Pyongyang take corresponding steps to build trust.
But Trump has rejected a step-by-step approach, saying sanctions must remain on North Korea until it agrees to give up all of its nuclear weapons.
Trump pressures...South Korea?
Making matters even more awkward for Moon, Trump is explicitly using the threat of North Korea to ramp up pressure on Seoul.
In a tweet last week, Trump said South Korea agreed to pay "substantially more" for the cost of U.S. protection from North Korea. Seoul quickly shot back, saying cost-sharing talks had not yet begun.
Trump has long complained South Korea isn't paying enough for the cost of the 28,500 U.S. troops stationed here. According to local media, the U.S. recently demanded South Korea increase its share by fivefold - a request that raised the eyebrows of some in Seoul.
Ahn Gyu-back, the chairman of the South Korean legislature's National Defense Committee, recently told VOA that while South Korea's relationship with the U.S. remains strong, Seoul cannot accept demands that are "beyond common sense."
"We can only do whatever we can do within our own capability, habit, and common sense," Ahn said.
Moon is also facing increasing domestic pressure to respond more firmly to North Korea's missile tests. Since May, Pyongyang has conducted seven tests of short-range ballistic missiles, which could reach all of South Korea.
The South Korean government has said the tests are not helpful. Other U.S. allies, including Japan and several European countries, say the missiles violate United Nations Security Council resolutions. But Trump says he has "no problem" with the launches, since the missiles cannot reach the United States.
Citing Trump's comments, North Korea's foreign ministry on Sunday defended the tests, comparing Seoul's complaints about the missiles to a "shy dog" who is barking "wildly."
North Korea has vowed to stop the missile tests after U.S.-South Korean military drills wrap up. But with Trump and Kim now openly playing off each other in order to pressure Seoul, and North Korea refusing to hold talks with the South, Moon risks finding himself on the outside looking in.
It's an awkward position for a man who was instrumental in bringing Trump and Kim together after the two leaders spent much of 2017 exchanging threats of annihilation.
Some in Seoul now fear time may be running out to resolve the U.S.-North Korean deadlock. "And if it isn't solved," warns Song, the South Korean lawmaker, "then it will get worse."