This week offered two starkly different snapshots of Japan-South Korea relations. An annual joint poll found public attitudes toward each other improving in both countries. Two days later, Seoul lodged a formal protest after Tokyo’s latest defense white paper reaffirmed the country’s claim to disputed islets in the Sea of Japan.

The contrasting developments highlight a central question: Has the recent improvement in bilateral ties become durable, or is it still vulnerable to the historical and political disputes that have repeatedly pulled the relationship backward? When Lee Jae Myung first took office as South Korea’s president last June, there were concerns that the return of a progressive administration in Korea would lead to a reverse course in Japan-Korea relations.

The last progressive government under Moon Jae-in witnessed the rise of the “No Japan” campaign in South Korea, fueled by domestic politics and historical enmity.