In an April 12, 2017 interview with The Wall Street Journal, President Trump recently stated the following:
Trump’s claim that Korea ‘actually used to be a part of China’Originally Posted by Donald Trump
Donald Trump accused of 'shocking ignorance' after suggesting Korea used to be part of China
While The Independent article does a crap job explaining history and mostly relays what South Korean newspapers have said, the Washington Post article at least mentions the Han Dynasty's commanders in northern Korea that lasted from the 2nd century BC until the Western Jin period of the 4th century AD, the Tang Dynasty's invasion of the Korean Peninsula in alliance with Silla (although failing to mention that the Tang occupied large portions of the former Goguryeo and Baekje states during the 7th century AD), and the Mongol-led Yuan Dynasty's conquest and subjugation of Goryeo in the 13th century AD, turning Korea into a neutered vassal state that not only paid tribute but was also heavily monitored and supervised by the Mongol rulers of Beijing (then called Dadu, or Khanbilaq).
Obviously Trump is wrong to have said "Korea actually used to be a part of China" when this is only partially correct. On that note, one should consider the fact that Goguryeo and Balhae extended into Manchuria, which is now part of the People's Republic of China, yet we do not say China was a part of Korea. Still, the facts are indisputable that the Chinese colonized what is now North Korea for centuries on end, beginning with the conquest of Wiman Joseon by Emperor Wu of Han in 109-108 BC. Yet they didn't just colonize it; they established prefecture-level governments there known as "commanderies" (郡, jůn) that were on an administrative level just below a province (州, zhōu). These Chinese commanderies came to an end in the 4th century AD when the Korean kingdom of Goguryeo conquered and absorbed them.
Clearly emperors Wen and Yang of China's Sui Dynasty were interested in reclaiming these territories and reestablishing these commanderies when they invaded Goguryeo in 598 and 612-614 AD, respectively. These campaigns were a total failure, yet China's subsequent Tang Dynasty, specifically under Emperor Gaozong of Tang, had much greater success in the Korean peninsula, if only for a few fleeting decades. With the aid of their Korean ally Silla, they managed to topple both Baekje in southwestern Korea in 660 AD and Goguryeo in northern Korea in 668 AD. The joint Tang-Silla allied forces fought against a Japanese invasion in 663 AD that aimed to restore their Baekje allies. Yet the Tang-Silla alliance came to an end in 670 AD when war broke out between the two. The conflict raged until 676 AD, during which Tang forces launched invasions into Silla. The Silla drove Tang forces out of former Baekje territories and Silla, all the way to the Taedong River in what is now North Korea. Tang forces remained there until 698 AD, when a former general of Goguryeo established the Balhae Kingdom and finally drove the Tang Chinese out of the Korean Peninsula (technically these were "Zhou" forces since this was during the reign of Empress Wu Zetian, an interregnum period for the Tang dynasty).
Spoiler Alert, click show to read:
Then we come to the Mongol invasion of Goryeo-period Korea during the 13th century AD. In campaigns stretching from 1231 to 1270 AD, the Mongols under Mongke and then Kublai Khan (founder of China's Yuan Dynasty) finally succeeded in subjugating Goryeo as a vassal (with periods of peace in between when Goryeo sent royal family members as hostages to the Mongol court). This client-vassal relationship lasted for the next eight decades. In that amount of time, the Korean Goryeo royal family was forced to marry into the royal family of the Mongol khans ruling from Beijing. Yet this was more than just a marriage alliance and tributary relationship, seeing how Mongol forces continued to garrison parts of Korea, such as Jeju Island. Kublai Khan also used Korea as a staging point for his two failed naval invasions of Japan.
After the fall of the Mongol Yuan Dynasty, the Ming and Qing dynasties maintained a much looser client-vassal relationship with Korea's Joseon kingdom, in that they did not bother to micromanage affairs of the Joseon court (and for that matter were unable to do so). The Ming respected the sovereignty of Joseon but still viewed it as a client state if not a fellow Confucian-ruled power. The Ming came to Joseon's defense in the 1590s when the Japanese invasion of Toyotomi Hideyoshi threatened to swallow the entire Korean Peninsula, with the ultimate aim of invading China. This is somewhat reminiscent of when US, South Korean, and NATO allied forces were on the cusp of taking all of North Korea in the early 1950s, only to have the army of the People's Republic of China come to the aid of their fellow communist Kim Il-Sung and push South Korean forces and NATO allies back to the 38th parallel north. China under Mao Zedong was keen on retaining their historical-based client in the Korean Peninsula, if not having a strategic alliance with a fellow communist power that was friendly to contemporary Chinese interests.
So, after taking all of this into consideration, should we continue to lambaste Trump for being incorrect? Or should we note the complexities here in regards to Chinese forays and occupations of at least parts of the Korean peninsula during the past two millennia, if not it's close tributary relationship that followed these invasions. I think South Korea has a right to defend its sovereignty like any modern nation, but this nationalist sentiment is often superimposed over historical reality when it is anachronistic and unnecessary. On the other hand, China has been rather provocative in creating the Northeast Project of the Chinese Academy of Social Sciences, which seeks to affirm that North Korea at the very least was rightfully part of the Chinese empire (and obviously shores up claims over Manchuria). At the very least, it is a fact that Imperial China incorporated parts of Korea into its empire from time to time. I think Trump's statement, while ignoring the nuance, is at least partially correct. He should have minced his words a little better, though, to avoid offending his allies in South Korea.