• A conservative victory for South Korea's upcoming presidential election could see the country adopt a rigid stance on North Korea and China, potentially igniting fresh tensions in the Asia-Pacific.
• Given North Korea's ongoing missile activity and anti-China sentiment at home, foreign policy matters are expected to affect public sentiment.
• With each candidate holding diverging views on relations with North Korea, China and the United States, there's a lot at stake for South Korea's geopolitical fate.

A conservative victory for South Korea's upcoming presidential election could see the country adopt a rigid stance on North Korea and China, potentially igniting fresh tensions in the Asia-Pacific.

Yoon Seok-youl of the conservative People Power Party and Lee Jae-myung of the ruling Democratic Party (DP) are the front-runners for the March 9 vote. A string of opinion polls conducted by Gallup Korea, a research company, show Yoon and Lee running neck and neck, indicating a tight race ahead. In one survey of 1,000 adults on Feb. 25, Lee's public approval rating stood at 38%, compared with Yoon's 37%. Another poll in early February showed the two tied at 35%. 

Economic issues, particularly housing, are at the forefront of this election. But given North Korea's ongoing missile activity and anti-China sentiment at home, foreign policy matters are also expected to weigh on public sentiment. With each candidate holding diverging views on relations with North Korea, China and the United States, there's a lot at stake for South Korea's geopolitical fate.

North Korea

Kim Jong Un's government has been ramping up missile tests as diplomatic talks with the United States and its allies remain at a standstill. This isn't a novel development, but against the backdrop of Russia's invasion of Ukraine, it adds to rising fears of regional unrest. Most recently, on Feb. 27, Pyongyang fired what likely was a medium-range ballistic missile, according to officials in South Korea and Japan.

In line with his conservative predecessors, Yoon demands North Korea first denuclearize before the two Koreas agree on peace pacts and economic assistance. In late November, he told the South Korean newspaper Kookmin Ilbo that he would consider canceling the 2018 Comprehensive Military Agreement, a diplomatic milestone of President Moon Jae-in's reign, if North Korea doesn't change its attitude.

In contrast, DP's Lee supports Moon's approach of diplomatic engagement and economic cooperation with North Korea as a means of initiating denuclearization. He also supports easing existing sanctions if North Korea complies. Unlike Yoon, Lee is also open to declaring an end to the Korean war in order to bring Pyongyang back to the negotiating table.

However, despite sharing similar perspectives, analysts said, Lee is unlikely to copy Moon's policies. "While Moon was personally heavily invested in engineering an inter-Korean summit, and trying to build sustainable, cooperative relations with North Korea, Lee is more likely to uphold the principle of peaceful coexistence while being reluctant to expend too much political capital on trying to achieve it, especially if Pyongyang is uncooperative," Jenny Town, a senior fellow at independent think tank Stimson Center, told CNBC. Town is also the director of the Center's North Korea-focused research arm, 38 North.

Further complicating matters is Yoon's emphasis on resuming joint military exercises with the United States. These have been scaled down since 2018, "owing to North Korea's perception of these manoeuvres as preparation for war," Fei Xue, Asia analyst at the Economist Intelligence Unit, told CNBC. A revival is thus likely to anger Kim Jong Un. Yoon's position is "harsh enough to make North Korea abandon diplomacy altogether, as it was the case during the tenures of Lee and Park," Khang X. Vu, a doctoral student and East Asian politics specialist at Boston College, wrote in a note published by the Lowy Institute.

China and the U.S.

A wave of anti-China uproar has been sweeping across South Korean media in recent weeks following controversies surrounding the Winter Olympics in Beijing. Combined with broader concerns about Beijing's aggressive stance toward its neighbors in the South China Sea and the Indo-Pacific, the Asian giant has become a central talking point in this election. South Korea's position on China is also closely linked to its relationship with the United States, given Beijing and Washington's historical rivalry, meaning Seoul often finds itself in a position of prioritizing one of the two superpowers. 

"Lee is expected to adhere to a relationship of strategic ambiguity with China, wanting to balance security and economic relations," said Town. Like Moon, Lee understands that he needs Chinese support on both the North Korea issue as well as on the economic front. "Lee Jae-myung is more concerned about China's economic influence on South Korea, and will therefore adopt a more neutral stance," echoed Xue. "However, the intensifying tensions between the US and China will make this approach increasingly difficult to hold," Xue added.

Yoon, meanwhile, seeks stronger security cooperation with the U.S., specifically calling for additional Terminal High Altitude Area Defense deployments, which is sure to spark economic punishment from China. The installation of the U.S. anti-missile system in South Korea led to a year-long standoff between Beijing and Seoul from 2016 to 2017, with South Korea's tourism, cosmetics and entertainment industries reeling from Chinese backlash. Yoon also wants to apply for membership of the Quadrilateral Security Dialogue as well as participate in the Five Eyes intelligence sharing program "despite possible China's opposition to such moves," said Xue. Yoon's willingness to overtly side with the U.S. will be questioned, however, "if or when China starts to apply pressure on Seoul," Town said.

Japan

Relations with Tokyo have worsened under the current Moon Jae-in administration owing to trade spats and unresolved issues over Japan's colonial rule over Korea from 1910 to 1945. The latter include matters such as Japan's procurement of South Korean women for military brothels. Kang Chang-il, South Korea's ambassador to Japan, said in January that bilateral ties were at their "worst" level since 1965.

That's expected to improve under a conservative regime. In a televised debate last month, Yoon said Seoul's relationship with Washington and Tokyo deteriorated because of "submissive diplomacy that is pro-China and pro-North Korea," adding that he would change that dynamic. Yoon is widely expected to set aside historical disputes with Japan in order to resolve bilateral trade conflicts and forge closer security cooperation, several experts told CNBC.

While Lee agrees on the importance for South Korea and Japan to improve bilateral relations and is open to talks, he insists that Japan make efforts to properly address historical disputes.

The nature of Asian geopolitics

While each candidate offers fundamentally different views on inter-Korean relations and U.S.-China rivalry, several analysts said the dynamics of Asia-Pacific security and politics don't allow for great shifts in foreign policy. 

"An increase in regional tension brought about by China's assertiveness, US efforts to contain China, or North Korea's long-range missile and nuclear tests, will shrink the number of policy options that the next South Korean president can pursue," Vu wrote in his note. "Unfortunately, such a deterioration in regional dynamics is increasingly likely."

Stimson Center's Town said: "Even in trying to cultivate deeper relations with other middle powers, as South Korea is currently trying to do to create some buffer for itself amid rising US-China rivalry, this is a long term process." She added: "In the near- to mid-term, South Korea will continue to find itself in a strategic dilemma as it works to navigate US-China competition while bolstering its own defences against significant improvements in North Korea's weapons capabilities."