During a March 9, 1977 news conference, Carter supported his interest in having a withdrawal of American troops from South Korea and stated he wanted South Korea to eventually have "adequate ground forces owned by and controlled by the South Korean Government to protect themselves against any intrusion from North Korea". Carter's withdrawal of troops was criticized by top military officials. On May 26, during a news conference, Carter said he believed South Korea would be able to defend themselves despite the lower number of American troops in the event of conflict. From June 30 to July 1, 1979, Carter held meetings with President of South Korea Park Chung-hee at the Blue House.
Carter said that the liberal wing of the Democratic Party did not support his policies the most. He said they were caused by Ted Kennedy's plan to replace him as president. Kennedy announced his candidacy in November 1979. Kennedy surprised his supporters by running a weak campaign, and Carter won most of the primaries and won renomination. However, Kennedy gave Carter weak support from the Liberal Democrats in the fall election. Carter and Vice President Walter Mondale were formally nominated at the Democratic National Convention in New York City.
Carter's campaign for re-election in 1980 was one of the most difficult. He faced strong challenges from the right (Republican Ronald Reagan), the center (independent John B. Anderson), and the left (Democrat Ted Kennedy). His campaign manager and former appointments secretary, Timothy Kraft, stepped down some five weeks before the general election because of an allegation of cocaine use. On October 28, Carter and Reagan participated in the only presidential debate of the election cycle. Though initially losing to Carter by several points, Reagan had a surge in polling following the debate.
Carter lost his re-election bid to Ronald Reagan in a landslide victory. Reagan won 489 of the electoral votes and Carter won 49. In the aftermath of the election, Carter said that he was hurt by the outcome of the election.
Shortly after losing his re-election bid, Carter told the White House press corps that he wanted his retirement to be similar than that of Harry S. Truman and not use his public life to make himself rich. In October 1986, his presidential library was opened in Atlanta, Georgia.
Carter built homes in the aftermath of Hurricane Sandy, and partnered with former presidents to work with One America Appeal to help the victims of Hurricane Harvey and Hurricane Irma in the Gulf Coast and Texas communities.
Carter attended the dedication of his presidential library and those of Presidents Ronald Reagan, George H. W. Bush, Bill Clinton, and George W. Bush. He delivered eulogies at the funerals of Coretta Scott King Gerald Ford, Theodore Hesburgh, and John Lewis. He has attended the state funeral of every former president since he left office: Nixon in 1994, Reagan in 2004, Ford in 2006 and Bush Sr. in 2018. When going to the inauguration of Donald Trump in 2017, he became the oldest former president to go to one.
In 1982, Carter founded the Carter Center, a non-governmental and non-profit organization with the purpose of spreading human rights and end human suffering. He wanted to help improve the quality of life for people in more than 80 countries.
In 1994, President Bill Clinton wanted Carter's help in a North Korea peace mission. Carter negotiated an understanding with Kim Il-sung, with whom he went on to outline a treaty. Carter traveled to North Korea to help the release of Aijalon Gomes in August 2010, successfully negotiating his release. In 2017, Carter said that he had offered himself to the Trump administration as a diplomatic envoy to North Korea to help create a peace treaty.
In October 1984, Carter was named an honorary citizen of Peru. Carter supported the country's elections in 2001, and offering support to the Peruvian government following a meeting with President of Peru Alan García in April 2009.
In his February 1986 talks with Tomás Borge, Carter helped push for the release of journalist Luis Mora and labor leader Jose Altamirano, while touring Nicaragua for three days.
Carter held a tour of Cuba in May 2002 that included meeting with Fidel Castro Carter toured Cuba again for three days in March 2011.
Carter's diplomatic efforts in the Middle East included a September 1981 meeting with Prime Minister of Israel Menachem Begin, a March 1983 tour of Egypt that included meeting with members of the Palestine Liberation Organization, and a December 2008 meeting with Syrian President Bashar al-Assad.
Carter traveled to Syria in April 2008, laying a wreath at the grave of Yasser Arafat in Ramallah and denying he had been contacted by the Bush administration in relation to meeting with Hamas leaders.
In July 2007, Carter joined Nelson Mandela in Johannesburg, South Africa, to announce his participation in The Elders, a group of independent global leaders who work together on peace and human rights issues. Carter wanted to travel to Zimbabwe to promote human rights in November 2008, but was stopped by President Robert Mugabe's government.
Carter held summits in Egypt and Tunisia in 1995–1996 to talk about violence in the Great Lakes region of Africa, and played a key role in negotiation of the Nairobi Agreement in 1999 between Sudan and Uganda.
During the presidency of George W. Bush, Carter stated his opposition to the Iraq War, and what he called an attempt on the part of Bush and Tony Blair to remove Saddam Hussein through the usage of "lies and misinterpretations". In May 2007, Carter stated the Bush administration "has been the worst in history" in terms of its impact in foreign affairs, Carter criticized the Bush administration's handling of Hurricane Katrina.
Though he supported President Barack Obama in the early part of his tenure, Carter criticized his use of drone strikes against suspected terrorists, Obama's choice to keep Guantanamo Bay detention camp open, and the current federal surveillance programs.
In July 2016, Carter announced his support of former Secretary of State Hillary Clinton's presidential nomination during the 2016 Democratic National Convention. Carter said that the impact of the 2016 election would "define the US for a generation". He originally supported Vermont U.S. Senator Bernie Sanders and voted for him during the primaries in 2016.
During the Donald Trump presidency, Carter supported immigration reform through Congress, and criticized Trump for his handling of the national anthem protests.
In September 2019, Carter said he would support an "age-limit" for presidential candidates.
In August 2020, he supported former Vice President Joe Biden for president during a video played at the 2020 Democratic National Convention.
Carter and Rosalynn Smith were married on July 7, 1946 in the Plains Methodist Church, the church of Rosalynn's family. They have three sons, one daughter, eight grandsons, three granddaughters, and two great-grandsons.
Carter and his wife Rosalynn are well known for their work as volunteers with Habitat for Humanity.
Carter's hobbies include painting, fly-fishing, woodworking, cycling, tennis, and skiing. He also has an interest in poetry.
Carter was also a personal friend of Elvis Presley. Carter and his wife, Rosalynn, met him on June 30, 1973, before Presley was to perform onstage in Atlanta. The day after Presley's death, Carter issued a statement and explained how he had "changed the face of American popular culture".
In 2000, Carter ended his membership with the Southern Baptist Convention, saying the group's ideas did not support with his Christian beliefs.