SEOUL — Caught between a rock and a hard place, Japan and Korea are threatening to shatter hopes of getting along. The rock is a pair of towering crags in the seas between them. The hard place is Japan’s claim to both of them.

In the face of efforts by Japanese and Korean leaders to bury historic differences, the ruckus over the islets shows why Japan and South Korea can’t stand one another. To the Koreans, they’re Dokdo, “solitary islands”; to the Japanese, they’re Takeshima, “bamboo islands.” The waters between Korea and Japan are the East Sea to the Koreans and the Sea of Japan to the Japanese.

Never mind that the Koreans have held the islets ever since the Japanese surrender at the end of World War II. The Japanese insist they’re Japanese, just as they do several small islands that, since the Soviet army captured them in the last week of the war, have been held by the Russians.

Name games aside, the islets are “clearly an integral part of Korean territory in terms of history, geography, and international law,” Korea’s foreign ministry said Friday, urging Japan to “scrap” its “sovereignty claim.”

Seoul fired off that indignant response after Japan’s defense minister, Nobuo Kishi, reiterated the exact same claim the Japanese have been making for years. The latest tit-for-tat may be same old, same old, but the timing endangers top-level talks to resolve festering problems dating from Japan’s rule over Korea between 1910 and 1945.

South Korea’s foreign minister, Park Jin, was in Tokyo this week warming over relations that nosedived during the presidency of the liberal Moon Jae-in, who stepped down in May after the election of the conservative Yoon Suk-yeol.

Mr. Park, on the first visit to Japan by a South Korean foreign minister in more than four years, said after getting back to Seoul that Mr. Yoon had made “a strong commitment to improving South Korea-Japan relations” and aspired for “a relationship of trust going forward in line with our common interests.”

Mr. Yoon “is rushing to mend years of troubled relations with the country’s key neighbor Japan,” a long-time correspondent for the old Far Eastern Economic Review, Shim Jae-hoon, wrote, “but the road ahead to reconciliation is littered with detritus of history that won’t be easy to negotiate.”

One issue that was definitely not on the agenda was ownership of Dokdo/Takeshima, which has one elderly inhabitant plus 40 members of South Korea’s national police force and six civilians manning a lighthouse. Slightly more than 100 yards apart, they cover about 46 acres of mostly solid rock rising more than 500 feet on one islet, about 300 feet on the other.

For all the rhetoric, the Japanese have never challenged Korea’s control militarily, but it’s well understood neither side will back down on claims that symbolize a legacy of bitterness on a wide range of issues.

The worst at the moment is a ruling in 2018 by South Korea’s “pro-Moon Supreme Court ordering Japan’s Nippon Steel to compensate four Korean men who had been drafted to work at its factory during World War Two,” Mr. Shim wrote on Asia Sentinel, a website. “Under this ruling, the court ordered the seizure of Japanese corporate assets in Seoul to compensate workers, raising the possibility of the court or claimants selling them off to raise cash.”

The issue of pay due laborers parallels that of compensation for the last survivors among thousands of “comfort women” forced by the Japanese to serve their troops in World War II. Claimants, whether demanding wages owed by Japanese companies or compensation for sexual exploitation, are dying off.

The Japanese insist all such matters were resolved in 1965 when Japan and Korea opened diplomatic relations and Japan paid Korea $500 million for “final settlement” of everything. The Koreans say they were misled into a deal that wasn’t fair.

Mr. Park, pressing for cooperation between Japan and Korea in vital areas like defense against North Korea, called for rapid solutions “considering Japan’s concerns about liquidation (of companies in Korea) and the advancing age of the victims.” Just as they refuse to give up their claim to Dokdo/Takeshima, however, the Japanese may be in no mood to make concessions. 

Yet another issue revolves around moves to revise if not do away with Article 9 of the Japanese post-war “peace” constitution banning Japanese troops from waging war overseas. If the article is revised, as many members of the ruling Liberal-Democratic Party are hoping, Japan’s Self-Defense Force would be freed to respond outside Japan to military threats from North Korea and China, and the defense budget would double from its present level of 1 percent of the country’s gross domestic product this year of $5 trillion-plus.

Koreans view the prospect of a significant increase in Japanese military strength with distinctly mixed feelings. On the one hand, Japan would bolster Korea’s defense against North Korea, which threatens both South Korea and Japan with nuclear-tipped missiles, and serve as a bulwark against Chinese support of the North in a second Korean War. On the other hand, Koreans with memories of the Japanese colonial era fear the renaissance of Japan as a major military power.

The Americans, of course, are attempting to persuade Korea and Japan to work together. “Japan’s defense modernization and a close trilateral relationship are not mutually exclusive,” a former director for east Asia on the National Security Council, Christopher Johnstone, said in an interview with Voice of America. “There’s nothing to be concerned about in Seoul about Japan’s defense modernization.”

As for Mr. Yoon, Mr. Shim wrote, “he is in no position to bargain or drag his feet as he urgently needs Japan’s help in gaining membership in the US-led Quad Security Dialogue, and Indo-Pacific Economic Framework which Tokyo and Washington are pushing to counter China’s expansionist posture in the region.”