For five years, South Korean President Moon Jae-in has cajoled his immediate neighbor to talk and encouraged cross-border exchanges. He has offered assistance to Pyongyang and promised more if only Kim Jong Un would halt his development of nuclear weapons.  

Elected in 2017 with high hopes, Moon's efforts have been to no avail.

Now, after the deeply conservative Yoon Suk-yeol won the presidential election to succeed Moon, analysts anticipate a very different bilateral dynamic.

The fear is that the two nations will return to outright confrontation rather than the uneasy coexistence that has characterized Moon's administration.

"Yoon has revived the conservatives' principled approach toward North Korea, which means he will be tougher by calling out and punishing provocative and illegal actions while keeping the door open to dialogue and diplomacy," said Duyeon Kim, a Seoul-based adjunct senior fellow for the Center for a New American Security, a bipartisan think tank headquartered in Washington, D.C.

Blind eye to bad behavior 

"The progressives like to front-load on concessions first and condone bad behavior, but the conservatives prefer tit-for-tat," she told DW.

"Yoon's advisers and supporters believe Moon's policies have given North Korea free range to advance its nuclear weapons capability."

As president-elect, Yoon has already received an in-depth briefing on security issues facing the nation, with North Korea and the situation in Ukraine topping the agenda, while a spokeswoman for the incoming leader expressed hope that North Korea would be willing to return to discussions on the complete denuclearization of the Korean Peninsula.

There are few signs that Kim is contemplating that course of action, however.

North Korea has already launched 10 missiles this year, with the US declaring that the most recent launch was a test of intercontinental ballistic missile technology.

Pyongyang has denied that assertion and claims it was a dry run for the launch of a spy satellite to monitor US units in the region, as well as those of "vassal forces."

In addition, there are indications that North Korea is carrying out work to return its Punggye-ri nuclear testing ground to operational status and satellite images have revealed that the Yongbyon nuclear complex is once again operating at full power.

On Monday, intelligence sources in the US and South Korea were quoted by Yonhap News as saying that North Korea was preparing to launch another ICBM, possibly as early as this week.

And while the March 5 test saw the missile climbing steeply after launch, reaching an altitude of 560 kilometers (348 miles) before a similarly steep descent into the ocean off the east coast, the next launch may test the distance the weapon can fly, meaning that a North Korean missile will once again fly over Japan.

Defenses stepped up 

Given that, Yoon is likely to quickly seek to resume joint US-South Korean military drills that were drastically reduced in scale or suspended entirely under Moon, to build up the South's independent defense capabilities and strengthen the deterrent provided by the military alliance with the US. 

There are a number of clear downsides, however, Duyeon Kim points out.

"All these measures will give North Korea an excuse to justify future weapons tests — which it would have done anyway even if a progressive South Korean was elected as president," she said. "And if more defensive weapons like missile defense batteries are deployed to the region, they will likely irritate Beijing too.

"Some of Yoon's desires will be either difficult or impossible for the [Joe] Biden administration to support, including the return of tactical US nuclear weapons," she said. "We will have to see whether and how Washington responds to Yoon's advisers' wish for a NATO-style nuclear sharing mechanism and the nuclear-powered submarines that Australia got."

Ties depend on North Korean response 

Rah Jong-yil, a former diplomat and head of the South Korean intelligence department charged with monitoring North Korea, has spoken with Yoon since his election win and believes the incoming president is "still formulating many of his policies, including those on North Korea."

"A lot of it depends on how North Korea reacts to the new South Korean leader and my initial impression was that he wants to give Pyongyang the chance to engage in talks and to build better relations," he said.

"At least in the initial phase of his presidency, given the problems that we see in Ukraine, with China over Taiwan and between Seoul and Tokyo, Yoon would be very happy not to have any problems with Pyongyang."

Nevertheless, Rah anticipates that Yoon's approach will be different to that of his predecessor, who was repeatedly accused of overlooking blatant provocations and snubs by the North out of hope that not criticizing the Kim regime would encourage Pyongyang to return to talks.

Rah says Yoon "will not go too hard on North Korea" and that he will be willing to meet Kim in person, if there is a chance of improving bilateral ties — but that he will be ready and willing to respond more forcefully when challenged.

Edited by: Srinivas Mazumdaru