Alex Neill, a senior fellow at defense think-tank the International Institute of Strategic Studies (IISS), recalled his surprise on visiting the South Korean Ministry of Defense in Seoul.

“Instead of seeing a large piece of artwork of a unified Korea, or the sacrifices of Korea and its allies in the Korean War, you are confronted by a massive picture of Dokdo,” the Briton said, referring to the South Korea-occupied islets in the Sea of Japan whose ownership is disputed by Japan. “I think anyone would be nonplussed about that.”

Indeed: In a region where North Korea and China loom over very close horizons, it is a natural expectation that democratic fellow-travelers and US allies South Korea and Japan would be close partners on defense.

In reality, they are gulfs apart.

Currently, South Korea has locked horns with Japan on territorial, diplomatic, judicial and even security fronts and is also at loggerheads with its only ally, the United States, over cost-sharing. But while South Korea risks isolation, a growing hole is gaping in Northeast Asia’s US-led democratic front.

The Japan-South Korea hate fest

Japan and South Korea have (separate) alliances with the US. But while the two countries share similar governance formats, economic systems and lifestyles, and both enjoy each others’ culture, from cartoons to cuisine, they are disunited politically.

After Japan’s 1910-1945 colonial rule over the peninsula, Seoul and Tokyo restored diplomatic ties in 1965 and Japan assisted Korea’s economic growth with capital and consulting. But since the early 1990s, after Korea democratized, they have been engaged in continuous historical and diplomatic spats.

The pattern is endless. South Korea slams Japan for imperial abuses in the first half of the 20oh century. Japan delivers apologies and offers compensation, but also authorizes revisionist school texts, while officials visit Tokyo’s controversial Yasukuni Shrine. Korea shoots back that Japan’s multiple apologies and payments are insincere.

Also dividing the two is a territorial issue. Dokdo (Takeshima in Japanese), sits in the Sea of Japan (which, not coincidentally, Korea insists should also be called “The East Sea”). It is claimed by both sides but occupied by Korea. In June 2018, following the halt of exercises aimed at North Korea, South Korean staged military drills with six warships and F-15 jets to practice the islet’s defense.

Bilateral relations have been particularly roiled since the current Moon Jae-in administration took power in Seoul in 2017 following the overthrow of the Park Geun-hye government after massive protests in 2016.

In 2015, the most emotive issue, the “comfort women” dispute, was resolved, on the government-to-government level, after an apology by Japanese Prime Minister Shinzo Abe was published globally and compensation paid. However, the Moon government, citing public opposition, has ceased to abide by the bilateral agreement and shuttered the foundation disbursing the Japanese monies.

In October, Tokyo was further irked when a Korean court ordered Japanese companies to pay Korean wartime laborers. Japan insisted that issue had been settled in the 1965 treaty, which included an $800 million compensation package. Tokyo is now demanding third-party arbitration – the first time it has called for that clause in the treaty to be exercised.

Security ties fracture

Things are also disintegrating on one front where relations had previously been amicable.

“For many years, Japanese and [South Korean] defense institutions have engaged with one another quite well at the operational level, including joint exercises, port calls, exchanges of defense cadets and personnel,” said Ryo Hinata-Yamaguchi, a Japanese visiting professor at Pusan National University in South Korea. “Relations are now affected by politics and it will be hard to upgrade or even exercise defense cooperation between the two.”

Last October, Seoul demanded a Japanese vessel attending a Korean naval review not fly its “rising sun” ensign, due to Korean sensitivities. The ship withdrew from the review.

In December, Tokyo accused a South Korean destroyer in the Sea of Japan of locking its target radar onto one of its maritime reconnaissance aircraft, and failing to respond to verbal radio inquiries. Seoul retorted that it had been using the radar in a search operation for a North Korean fishing boat; called the Japanese crew’s English incomprehensible; and accused Japan of buzzing its vessel at danger-close ranges.

The various issues may result from Moon’s populist stance in a nation where anti-Japaneseism is strong.

“This is kind of a scapegoat for the Moon government, amid economic and environmental problems stoke anti-Japanesesim,” said Daniel Pinkstone, an American expert on international relations at Troy University, referring to the unemployment and pollution issues that are slashing Moon’s ratings. “I think it is short-sighted. This does not serve Korea’s interest, but people can play to nationalist and anti-Japanese sentiment.”

Both sides released YouTube footage stating their respective cases in the radar dispute; general-level talks in Singapore failed to find a breakthrough. Seoul has since accused Tokyo of three separate buzzing incidents. Both sides now seem locked in an escalatory spiral.

On Saturday, Japan announced the cancellation of a spring port call by its ships. On  Monday, South Korea announced the cancellation of a bi-annual admiral-level visit to Japan.

“Moon is using the Japanese issue for domestic support,” said Yang Uk, a Korean defense specialist at Asan New University. “And for Japan, Abe will also use this.”

Making matters worse, the customary intermediary between the squabblers – the United States – is absent. “There is no assistant secretary of state for Asia-Pacific, no secretary of defense,” said Pinkston. “It seems like a lot of turmoil in DC.”

Seoul, Washington battle over troop costs

Meanwhile, Seoul and Washington have failed to reach an agreement on the cost-sharing burden for the 28,500 US troops stationed in South Korea, despite holding 10 rounds of talks since last March.

Washington reportedly demands $1 billion; Seoul refuses to pay more than KRW1 trillion ($894 million). As a result, according to a story citing a single unnamed source that has transfixed South Korea, the US has threatened to pull its troops out of the country. This is despite Seoul deploying a total defense budget of $42 million for 2019, and despite shouldering some 90% of the $10.8 billion costs of a brand new air-land-sea base complex in Pyongtaek, 65 kilometers south of Seoul; it the largest American base outside the US.

The negotiations are, “really tough – this is an extreme I have not seen before,” said Yang. Worried Korean officials have reportedly sought to enlist the support of US Secretary of State Mike Pompeo to smooth over the dispute.

However, US President Donald Trump has long been insisting that allies share a larger chunk of defense burdens, while his dismissive approach toward long-held alliances was one reason behind the resignation of ex-US Defense Secretary Jim Mattis.

“This is so Trump! The international politics of the United States are governed by domestic politics,” said Yang. “Trump wants to show the US people and all the other allies in Japan and even in Europe that he pulled off this kind of deal… this is one of the key battles for Trump.”

Yang believes the threat of withdrawal is a bluff but expects Washington to “make it as real as possible [though] in a strategic sense, it is nonsense,” he said.

But some experts truly fear that, unless Seoul caves on payments, Trump might just seek a sudden pullout of US troops.

“What is troubling is the marginalism of the inter-agency process,” said Pinkston, referring to Trump’s recent Syrian decision. “If you are going to make a big decision like that, you get the experts and have an internal debate and think it through, but [Trump] gets out of bed, gets on Twitter and blurts it out. That is dangerous, in my view.”

The crumbling US-led front in Northeast Asia

None of the foregoing developments look positive for the US-led security front in Northeast Asia – already undercut by the lack of an alliance linking Seoul, Tokyo and Washington.

“The absence of a complete alliance triangle certainly ups the inconvenience for the US as it inhibits proper coordination and coherence to mount credible deterrence and containment measures against the threats in the region,” said Pusan University’s Hinata-Yamaguchi.

Currently, the only security agreement binding Japan and South Korea is an intelligence-sharing pact, and the workings of that arrangement are questionable. “The US is the ticket window for intelligence sharing,” said Neill of IISS. “The inability of the Japanese and Koreans to work together is not encouraging.”

Currently, the only security agreement binding Japan and South Korea is an intelligence-sharing pact, and the workings of that arrangement are questionable

And even this minimal arrangement may evaporate: A South Korean lawmaker has proposed that the agreement be unilaterally scrapped.

Meanwhile, Trump keeps his eyes on the cash register – even though removing troops from South Korea and Japan and stationing them in the US would be more expensive.

For South Korea, the broader risk it faces as it takes on Japan and faces down Washington is ending up friendless in a tough neighborhood. While Tokyo has its alliance with Washington and is proactively reaching out to Canberra, Brussels and even New Delhi, Seoul’s only ally is Washington.

“In every strategy you have to have an exit strategy, but his kind of approach gives Moon no exit at all,” said Yang.