From 1961, he spent almost 30 years as one of the leaders of the South Korean opposition, and one of the most powerful rivals to the authoritarian regimes of Park Chung Hee and Chun Doo-hwan.

He was elected to the National Assembly at the age of 25, the youngest person in Korean history, and served as a nine-term lawmaker, working as a leader with Kim Dae-jung and the democratic camp.

He was inaugurated on 25 February 1993, and served a single five-year term, presiding over a massive anti-corruption campaign, the arrest of his two predecessors, and an internationalization policy called Segyehwa.

This caused him to have one of the lowest approval ratings of any incumbent president in the history of South Korea at 6%, from a historical high of 97%, until Park Geun-hye surpassed Kim at 1–3% during the political scandal in 2016.

[5] A few months after his electoral victory, Kim left his party and joined the opposition when Rhee attempted to amend the constitution of South Korea.

It was the biggest demonstration since the Syngman Rhee presidency, and spread to nearby Masan and other cities, with students and citizens calling for an end to the dictatorship.

[9] The Bu-Ma Democratic Protests caused a crisis, and amidst this chaos Park Chung-hee was assassinated on 26 October 1979 by KCIA Director Kim Jae-gyu.

[7] Kim's decision angered many democratic activists and politicians such as future president Roh Moo-hyun, who considered him a traitor but he maintained his political base in Busan and Gyeongsang.

As the candidate of the governing party,[1] he defeated Kim Dae-jung and businessman Chung Ju-yung, the boss of the chaebol group Hyundai in the 1992 presidential election.

This also made it difficult for chaebols to seek government favours by remitting money to politicians and officials under false and anonymous names, drastically curbing such practices.

[15] He had his two predecessors as president, Chun and Roh, arrested and indicted on charges of corruption and treason for their role in military coups, although they would be pardoned near the end of his term on advice of president-elect Kim Dae-jung.

[13] Kim also granted amnesty to 41,000 political prisoners in March 1993 just after taking office,[16] and removed the criminal convictions of pro-democracy protesters who had been arrested during the Gwangju massacre in the aftermath of the Coup d'état of December Twelfth.

"[17] During his administration, Kim viewed chaebols that monopolized importing certain resources or products and/or predominated certain markets they were "large enterprises" in as outdated parts of the era before his presidency and empowered by lax policies from the prior governments.

[17] In addition to curbing corrupt practices of the chaebols, Kim encouraged them to become leaner and more competitive to succeed in the global economy, in contrast to the state-directed economic growth model of the preceding decades.

[19] In 1994, when American president Bill Clinton considered attacking Nyongbyon, the centre of North Korea's nuclear program, Kim advised him to back down, fearing a war.

A US aircraft carrier and a cruiser had been deployed near South Korea’s east coast in preparation for a possible airstrike and the United States planned to evacuate Americans, including US troops and their families, Kim said in a memoir.

He understood that South Korean cities would be bombarded first by North Korea in the event of a strike and thought it necessary to stop any move that could start a war.

During that time, there was a haste by chaebols to compete and expand on the world stage, and Kim's 1993 financial reforms which allowed for the growth of merchant banks and short term loans fuelled increased borrowing by these companies.

The Hanbo scandal which involved Kim's son in early 1997 exposed South Korea's economic weaknesses and corruption problems to the international financial community.

He blamed companies for borrowing too much, workers for demanding too much pay and conceded that his government did not implement strong reforms on its own due to pressure from special interest groups.

His term ended on 24 February 1998, and he was succeeded by his political rival Kim Dae-jung who defeated the ruling conservative party in the 1997 South Korean presidential election.

From April 2002 to 2007, he dedicated himself to research, taking up a position as a Distinguished Professor at Waseda University where he had previously (1994) received an honorary Doctor of Laws degree.

Kim also differed from the more ideologically polarized ratings of other presidents by showing a remarkably similar evaluation between supporters of the two major parties, as well as between self-described conservatives, moderates, and progressives.

A humorous anecdote arose from another of his public speeches where audiences were said to have been surprised to hear that he would make Jeju a world-class 'rape' (관광, 觀光 [gwan gwang, tourism] > 강간, 強姦 [gang-gan, rape]) city by building up an 'adultery' (관통하는, 貫通- [gwantonghaneun, going-through]) > 간통하는, 姦通- [gantonghaneun, adulterous]) motorway.