With US President-elect Joe Biden set to enter the White House on Jan. 20, calls are rising here for Seoul to craft an approach befitting his emphasis on “principled diplomacy.”

Under a Biden administration, the South Korea-US alliance will certainly be free of much of the uncertainty that has overshadowed it during President Donald Trump’s bumpy four-year term.

Still, President Moon Jae-in’s government might find Biden’s team more delicate or difficult to deal with than the Trump administration.

In an article that he contributed to a local news agency last month, Biden pledged to strengthen the alliance with South Korea, rather than “extorting Seoul with reckless threats to remove our troops” from the country. Trump appears to have been using the possibility of cuts to US Forces Korea as a bargaining chip in the prolonged talks between the allies on how much Seoul should pay for the upkeep of the 28,500-strong USFK.

Biden also said he would “engage in principled diplomacy and keep pressing toward a denuclearized North Korea.”

The former US vice president has downplayed the three summits between Trump and North Korean leader Kim Jong-un as having achieved nothing, except giving Kim the global recognition that he had long sought.

Instead of the top-down formula favored by the Trump administration for negotiations with the North, Biden is expected to choose working-level engagement to work out a concrete road map for dismantling the recalcitrant regime’s nuclear arsenal.

Biden’s stance means that Moon and his aides would have little room to push for what they call the Korean peace process without substantial progress in denuclearizing the North.

In a prerecorded speech delivered at an international peace forum, held Friday on the southern island of Jeju, Moon pledged that South Korea would never cease its efforts to establish permanent peace on the peninsula and achieve denuclearization.

But he made no direct mention of the need to adopt a formal declaration ending the 1950-53 Korean War, which ended in an armistice. He had repeatedly suggested the idea in previous addresses, calling it an essential step to prompt Pyongyang to move toward denuclearization.

Moon’s reserved stance at the peace forum seemed to reflect the recognition that a Biden administration would be more resolute than its predecessor in rejecting concessions to Pyongyang, such as an end-of-war declaration, ahead of significant progress toward scrapping its nuclear programs.

During a virtual consultation with his US and Japanese counterparts Friday, Suh Hoon, director of national security at South Korea’s presidential office, called for the resumption of high-level dialogue between Washington and Pyongyang on the occasion of the US election.

Seoul now needs to focus on attuning itself with a Biden presidency to ensure the complete denuclearization of the North, rather than relying on the possibility of Washington and Pyongyang reaching an inconclusive deal in a top-down manner.

Given its previous patterns of conduct, North Korea might attempt to escalate tensions on the peninsula in an effort to size up the intentions of the next US administration even as it is still formulating its policies toward the totalitarian state.

In this regard, Seoul and Washington need to put their alliance on a more solid footing by restoring the joint military drills that have been scaled down or suspended since Trump held his first summit with Kim in Singapore in 2018.

Under a Biden presidency, South Korea might find it more difficult to walk a tightrope between the US and China amid the escalating rivalry between the two superpowers.

In his article, Biden described the South as a strong regional ally of the US to “advance our shared prosperity, values and security, and to meet global challenges.”

With an emphasis on a close network of allies and partners against China, a Biden administration is expected to draw Seoul into the US fold in a more principled and sophisticated way than the Trump administration.

Moon and his aides have been seeking to keep an equal distance from the US, its traditional ally, and China, its largest trading partner. It is clear that Seoul cannot allow its vital security interests to be undermined for whatever profits its economic partnership with China might bring.

They would do well to recall Biden’s words during his 2013 visit here as vice president, when he said “it has never been a good bet to bet against America.”