SEOUL • Buffeted by the currents of diplomacy, South Korea is sometimes described as a "shrimp between two whales", and United States President Donald Trump has touched nerves with remarks that the peninsula "used to be part of China".
The comments came after Mr Trump hosted Chinese President Xi Jinping at his Mar-a-Lago retreat in Florida. As the pair discussed ways to curb North Korea's nuclear ambitions amid mounting tensions, Mr Trump told the Wall Street Journal, Mr Xi "went into the history of China and Korea".
"And you know, you're talking about thousands of years... and many wars. And Korea actually used to be a part of China," Mr Trump went on.
The exact details of what Mr Xi said and whether Mr Trump accurately represented him are not known, but South Koreans are wary of Chinese expansionism, and politicians, historians and citizens have been outraged.
Beijing is Pyongyang's sole major ally and Washington wants it to do more about the North's nuclear and missile programmes, while the US has a security alliance with South Korea and stations more than 28,000 troops there to defend it.
If Trump really conveyed Xi's words correctly, it is nothing but a grave challenge to the identity of the Korean people.
SEOUL'S MAJOR DAILY, THE JOONGANG ILBO
The Korean peninsula has been heavily influenced by China politically and culturally for centuries.
While its ruling kingdoms sometimes paid tribute to their giant neighbour, South Korean historians stress they did not come under its territorial control, despite repeated invasions. Seoul's Foreign Ministry spokesman countered: "The fact that Korea was not part of China for thousands of years... is a clear historical fact acknowledged by the international community."
Chinese Foreign Ministry spokesman Lu Kang declined to confirm the details of Mr Xi's wording, saying that: "The Korean people should not be worried about it."
But Seoul's major daily, the JoongAng Ilbo, said South Koreans had been "dumbfounded" by the Chinese leader. "If Trump really conveyed Xi's words correctly, it is nothing but a grave challenge to the identity of the Korean people," it said.
South Korean historians and activists rallied outside the Chinese Embassy last Friday to protest against Mr Xi's "absurd remarks", Yonhap news agency reported.
Seoul and Beijing are already at loggerheads over the deployment of the US missile defence system Thaad to the South to guard against threats from the North. Beijing has imposed a series of moves, including a ban on group tours to the South and suspensions of South Korean businesses in China.
South Korea's top-selling Chosun newspaper turned on both leaders in an editorial on Friday, castigating Mr Xi for his "pre-modern expansionist view" and Mr Trump for a lack of awareness of diplomatic sensitivities.
The row came after South Koreans were dismayed by the revelation that the US aircraft carrier Carl Vinson and a supporting battle group were still thousands of kilometres from the peninsula, despite the White House saying it was dispatching them to the area.
Mr Trump had described the vessels as an "armada" and "very powerful" and the revelation drew jeers and disappointment.
The carrier controversy illustrated Mr Trump's "unpredictable behaviour" that could lead to "disastrous events", the Kyunghyang daily said.
"We are worried whether the Trump administration... can properly handle a crisis on the Korean peninsula," it added. "The South Korean government should brace itself against the 'Trump Risk'."