[1] At the 2009 G20 London summit, then-U.S. President Barack Obama called South Korea "one of America's closest allies and greatest friends.

[3][4] In June 2023, South Korean President Yoon Suk Yeol said that he had upgraded the country's alliance with the United States to one that is "nuclear-based" in the face of North Korea's growing military threat.

We will actively work to safeguard the freedom of the people of Ukraine and support their efforts in reconstruction" in a speech to the United States Congress.

[15] Each half was polarized politically: the USSR-backed North was led by the Communist Party, while U.S. General John Hodge handpicked far-right Syngman Rhee to lead the South.

[14][17] Cross-border skirmishes and raids at the 38th Parallel escalated into open warfare when the North Korean forces invaded South Korea on June 25, 1950.

In 1953, at the end of the Korean War, the number of prostitutes in South Korea was estimated as about 350,000, with about 60 percent working near U.S. military camps.

In July 2000, the Eighth U.S. Army apologized for an incident where formaldehyde, a toxic fluid, was released into the Han River in February of that year.

[29] In a report released in 2017 detailing spill incidents from 1995 to 2015 at the US garrison in Yongsan, South Korean environmentalist groups expressed concern about the lack of transparency and the possibility of continued water contamination, as well as who would take responsibility for cleanup of the site.

[31] The Government of South Korea banned imports of U.S. beef in 2003 in response to a case of mad cow disease in Washington state.

[32][33] At around 7:40 a.m. on March 5, 2015, United States Ambassador to South Korea Mark Lippert was attacked by a knife-wielding man at a restaurant attached to Sejong Center in downtown Seoul, where he was scheduled to give a speech at a meeting of the Korean Council for Reconciliation and Cooperation.

[34] The assailant, Kim Ki-jong, is a member of Uri Madang, a progressive cultural organization opposed to the Korean War.

[35] He inflicted wounds on Lippert's left arm as well as a four-inch cut on the right side of the ambassador's face, requiring 80 stitches.

[34] Kim has a record of militant Korean nationalist activism; he attacked the Japanese ambassador to South Korea in 2010 and was sentenced to a three-year suspended prison term.

[42] The rollout of the Terminal High Altitude Area Defense (THAAD) has been met with domestic opposition in South Korea.

In 2009, South Korea and the United States pledged to develop the alliance's vision for future defense cooperation.

[51] At a Cabinet meeting in Seoul on 10 July 2018, the government decided not to hold that year's Ulchi drill, scheduled for June 2018.

The Government said the decision was made in line with recent political and security improvements on the peninsula and the suspension of South Korea-U.S. joint military exercises.

[53] His approach to North Korea is similar to Kim Dae-jung's Sunshine Policy, which only continued up to the Roh Mu-hyun's administration.

[54] On 12 June 2018, during the 2018 Trump–Kim summit, U.S. president Donald Trump and Kim Jong Un signed a Joint Statement which reaffirmed the Panmunjom Declaration.

Harris, a former head of the U.S. military's Pacific Command, has expressed his resolve to work as an ambassador to strengthen the alliance between the United States and South Korea.

[57] In terms of American leadership, Bill Clinton and George W. Bush both emphasized the Middle East over North Korea.

Clinton had deep emotional ties with Israel but neglected North Korea issues and never built strong personal relations with South Korean leaders.

Biden said: "A nuclear attack by North Korea against the United States or its allies and partners is unacceptable, and will result in the end of whatever regime were to take such an action."

In talks with U.S. Admiral Samuel Paparo, they agreed to hold a second "Freedom Edge" exercise and expressed concerns about the security risks posed by North Korea-Russia military collaboration.

[67] According to Pew Research Center, 84% of South Koreans have a favorable view towards the United States and Americans (ranked within top 4 among the countries in the world).

[70] On the political side, the United States supported South Korea after 1945 as a "staunch bastion against communism", even when the ROK itself was ruled by a US-backed dictatorship.

[72] According to a 2014 BBC World Service Poll, 58% of South Koreans view U.S. influence positively, the highest rating for any surveyed Asian country.

[76] South Korea's export-driven economy and competition with domestic U.S. producers in certain fields of products have led to some trade friction with the United States.

[82] In July 2024, Pamela Melroy, Deputy Administrator of the NASA, visited South Korea to discuss space cooperation.

KCON, the world's largest Hallyu (Korean Wave) festival (organized by CJ ENM), surpassed 1.5 million cumulative on-site visitors by the 18th edition.