The well-worn phrase “The enemy of my enemy is my friend” has ancient roots.  It dates back 7,000 years to the Sanskrit literature of India’s Vedas. The Romans and the Koran adapted it to their political needs.

In Modern times it has been repeatedly applied. Possibly the most famous examples are Churchill and Stalin, and Mao and Nixon.

This weekend President Joe Biden will use the well-worn diplomatic axiom to try and persuade the leaders of South Korea and Japan that they should bury deep-rooted historical animosities to unite against the common enemies China, North Korea and Russia.

All three leaders will gather at Camp David on the edge of the Blue Ridge Mountains. They are expected to issue a communique agreeing to closer economic ties, intelligence sharing, a Tokyo-Seoul-Washington crisis hotline, a first ever joint statement of principles and trilateral military exercises.

What they will NOT do is agree to a formal treaty. Neither will Japanese Prime Minister Fumio Kishida formally apologise for Japanese atrocities committed before and during World War two.

There are lots of good and obvious reasons for Japan and South Korea to be friends. Both of them are threatened by China and North Korea and, to a lesser extent Russia. From the US point of view there are 85,000 American troops costing an estimated $15 billion. Washington desperately wants Seoul and Tokyo to shoulder more of the burden.

The South Koreans and Japanese have the means to assume a bigger role but until recently have lacked the will. Japan is the world’s third largest economy and fourth largest military establishment. Fast-growing South Korea is not far behind, ranking 13^th in the world GDP list and sixth on the size of its defense establishment.

Only 120 miles across the Sea of Japan separates the two countries, but only four percent of South Korea’s trade is with Japan. Its biggest trading partner is with North Korea’s protector China.

All the above explains why South Korean President Yoon Suk-Yeol has taken the initiative to mend broken fences with Tokyo. He recently invited Japanese Prime Minister Fumio Kishida to visit Seoul and on the 78th anniversary of Korean independence from Japan he described his country’s former colonial masters as “partners.”

However, Yoon’s pro-Japanese diplomacy has not gone down well with South Korean voters. A recent poll showed that 60 percent still distrust Japan and oppose closer relations.

There are reasons. In 1910 Japan invaded and annexed the Korean Peninsula. By the 1930s half the country’s agricultural land was owned by Japanese landlords and Japanese merchants controlled the country’s markets.

When Japan invaded Manchuria in 1931, Korea became the main thoroughfare for attacking Japanese troops. But the real problems started after Pearl Harbour. During World War Two an estimated two million Koreans were transported to Japan to work as slave labourers in Japanese factories. An estimated four million remained in Korea to work as slaves in mines and factories.

Perhaps the most emotive atrocity was the Japanese “recruitment” of the euphemistically named “comfort women”. They were, quite simply prostitutes. Up to 500,000 Korean women were forced into prostitution to satisfy the sexual needs of the Japanese army.

The Japanese have never apologised for these atrocities. In fact, many leading members of the ruling Liberal Democrat Party have complained that the South Koreans should be grateful for the roads, railways and factories that Japan built in Korea.

Kishida made a half-hearted attempt at an apology during his recent visit when he expressed “sympathy” for Korea’s “painful past.” His comment was attacked by parliamentary colleagues and dismissed by many South Koreans as a useless sop.

Kishida’s lack of support explains why most of the diplomatic running is being done by Presidents Yoon and Biden. Yoon is seriously worried about North Korea and China and accepts improvement of Japanese-Korean relations is a diplomatic necessity. His views lack public support, but he has another three and a half years until the next election where as Kishida could face a snap poll at any time.

For Biden, a US-brokered rapprochement between America’s two closest allies in Asia would be a diplomatic coup. Donald Trump tried to achieve the same. He failed. This must make Biden’s success all the sweeter.

* Tom Arms is foreign editor of Liberal Democrat Voice and author of “The Encyclopaedia of the Cold War” and “America Made in Britain".