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South Korea sees “red line”

August 18, 2017 | Expert Insights

The South Korean President Moon Jae-in has announced that North Korea would be crossing the “red line” if it mounts a nuclear warhead on an intercontinental ballistic missile (ICBM).   


Before Korea was divided into two nations, it was occupied by Japan in 1910. In the final days of World War II, Soviet Union declared war on Japan and advanced towards Korea. The US fearing that the Soviets would take over all of Korea, requested it to cease its military actions. Thus, Seoul and the southern part of Korea came to be occupied by US forces.  By 1948, Korea had been divided into two factions with Kim II-sung, as Prime Minister of North Korea.

In 1950, North Korean forces advanced to South Korea, occupying a large portion of it. This resulted in the US entering the conflict along with the United Nations to defend South Korea. The US forces were successful in pushing back the North Korean military and in 1953 an armistice was proposed and signed.

However, a peace treaty was never signed and thus the war never really ended. This is famously referred to as the “Forgotten War.” The two countries have since had a fractious relationship.

In July 2017, North Korea successfully tested an ICBM twice. According to experts, both could reach the United States. A confidential intelligence report leaked to the media has now stated that North Korea can now build nuclear bombs small enough to fit on missiles.  South Korea has condemned these tests and has conducted multiple joint military exercises along with the US in retaliation.


Moon Jae-In has consistently sought for dialogue with North Korea to resolve the conflict between the two nations. During a news conference marking his 100 days in office, he said that weaponizing an ICBM would be the red line. He said, “I would consider that North Korea is crossing a red line if it launches an intercontinental ballistic missile again and weaponizes it by putting a nuclear warhead on top of the missile.”

He also noted that the US President Donald Trump has promised to seek South Korea’s approval before taking any action against North Korea. He additionally affirmed that war was not an option, unless North Korea escalates. He noted, “Military action on the Korean peninsula can only be decided by the Republic of Korea. The U.S. and President Trump promised no matter what options they use, they will sufficiently consult with South Korea and get consent. This is a firm agreement between South Korea and the U.S. People can be assured and trust that there will be no war.”

Recently, North Korea has seemingly walked back on its threat to attack Guam, a US territory, thus de-escalating tensions.


Our assessment is that any military conflict between the US and North Korea would put the security of Seoul in danger. It is wise for the US to have committed to seek South Korea’s approval before taking any action in matters related to the stand-off with North Korea. 

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