Seoul’s top national security officials agreed during their meeting last week to step up efforts to improve South Korea-Japan relations that have long been strained by disputes over the history of the two countries. Their agreement follows President Moon Jae-in’s suggestion last month that his government would handle pending issues with Tokyo in a more flexible manner to forge a forward-looking bilateral partnership.

Ties between the two nations have sunken to one of its lowest ebbs over issues stemming from Japan’s 1910-45 colonization of the peninsula, which have spilled over to the economic and military realms in recent years.

In the eyes of critics, the Moon administration was negligent in seeking to find diplomatic solutions to historical discord with Tokyo, letting them get complicated by court rulings here. Some of Moon’s associates and ruling party lawmakers appeared to attempt to fuel anti-Japanese sentiment in a bid to rally voters ahead of last April’s legislative elections.

Seoul’s professed shift in its approach to the frayed ties with Tokyo seems prompted partly by Washington’s renewed push to strengthen trilateral cooperation with its two key Asian allies to counter nuclear threats from North Korea and keep a rising China in check. US President Joe Biden’s administration has named the North as one of the most serious challenges facing the US, while calling China as its largest strategic competitor in the region and world. In phone talks with his South Korean counterpart Chung Eui-yong on Friday, US Secretary of State Antony Blinken stressed the importance of continued cooperation among the US, South Korea and Japan, while pledging full partnership to strengthen the Washington-Seoul alliance.

Seoul appears concerned that estranged ties with Tokyo would hamper smooth consultations with Washington on how to deal with Pyongyang.

The Biden administration has said it will closely work with South Korea, Japan and other allies in choosing the best tools to be used against the North through a thorough review of policy approaches to the recalcitrant regime. This stance contrasts with Biden’s predecessor Donald Trump’s pursuit of a deal with North Korean leader Kim Jong-un on the totalitarian state’s denuclearization. Tokyo was sidelined from the process of Trump-Kim talks, which were initially brokered by the Moon administration.

North Korea has refused to discuss its denuclearization since the second summit between Trump and Kim in Hanoi in 2019 ended with no deal due to differences over the scope of measures to be taken by Pyongyang to get a significant sanctions relief from Washington.

In a reflection of their wishful thinking, Moon and his aides have expressed hope the Biden administration will start from Trump’s legacy to reach an agreement with the North, which is needed to carry forward their peace agenda for the peninsula.

It has yet to be seen how serious the Moon administration will be in turning its rhetoric on improving ties with Tokyo into substantial action. It is also important for Japan to respond actively to South Korea’s effort to mend bilateral relations, with its leaders refraining from using the prolonged discords with Seoul to their domestic political advantages.

But any endeavor by Seoul to improve relations with Tokyo would prove to be of little help for its bid to draw US support for its reconciliatory approach to the North. The Moon administration is criticized for being preoccupied with inter-Korean reconciliation at the risk of ignoring threats from Pyongyang’s ever-evolving nuclear arsenal.

A US State Department spokesperson said Friday North Korea’s continued advancement of nuclear weapons and ballistic missiles made it “an urgent priority for the US,” stressing Washington’s commitment to the denuclearization of the North.

Calling for an early resumption of dialogue with Pyongyang, officials in the Moon administration have said Kim still intends to denuclearize his country. But it is a more sensible judgment that Kim will never give up his nuclear arms because he believes they are key to the survival of his regime.

A persistent implementation of tight sanctions on the North is crucial to pressure him to abandon his nuclear arsenal before the North’s crumbling economy collapses altogether. If necessary, incentives might be considered to help ease the plight of North Korean people from a humanitarian viewpoint.

A close Seoul-Tokyo partnership under the auspices of Washington is needed to carry out such concerted efforts toward the complete denuclearization of the North.