Shortly after losing his re-election bid, Carter told the White House press corps of his intent to emulate the retirement of Harry S. Truman and not use his subsequent public life to enrich himself.
In 1982, Carter founded the Carter Center, a non-governmental and non-profit organization with the purpose of advancing human rights and alleviating human suffering, including helping improve the quality of life for people in more than 80 countries.
In 1994, President Bill Clinton sought Carter's assistance in a North Korea peace mission, during which Carter negotiated an understanding with Kim Il-sung, who he went on to outline a treaty with that he announced to CNN without the consent of the Clinton administration to spur American action. Carter traveled to North Korea to secure the release of Aijalon Gomes in August 2010, successfully negotiating his release. Throughout the latter part of 2017, as tensions between the US and North Korea persisted, Carter recommended a peace treaty between the two nations, and confirmed he had offered himself to the Trump administration as a willing candidate to serve as diplomatic envoy to North Korea.
In October 1984, Carter was named an honorary citizen of Peru by Mayor of Cusco Daniel Estrada after traveling to Machu Picchu, Carter endorsing the country's elections in 2001, and offering support to the Peruvian government following a meeting with President of Peru Alan García at Government Palace in Lima in April 2009.
In his February 1986 talks with Tomás Borge, Carter secured the release of journalist Luis Mora and labor leader Jose Altamirano, while touring Nicaragua for three days.
Carter conducted a tour of Cuba in May 2002 that included meeting with Fidel Castro and meeting political dissidents such as the AIDS sanitarium, a medical school, a biotech facility, an agricultural production cooperative, and a school for disabled children. 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, a December 2008 meeting with Syrian President Bashar al-Assad, and a June 2012 call with Jeffery Brown in which Carter stressed Egyptian military generals could be granted full power executively and legislatively in addition to being able to form a new constitution in favor of themselves in the event their announced intentions went through. In 2006, Carter stated his disagreements with the domestic and foreign policies of Israel while saying he was in favor of the country, extending his criticisms to Israel's policies in Lebanon, the West Bank, and Gaza. 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.
Carter with William Hague, Martti Ahtisaari, and Lakhdar Brahimi from The Elders group in London, July 24, 2013.
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. Following the announcement, Carter participated in visits to Darfur, Sudan, Cyprus, the Korean Peninsula, and the Middle East, among others. Carter attempted traveling to Zimbabwe in November 2008, but was stopped by President Robert Mugabe's government.
Carter held summits in Egypt and Tunisia in 1995–1996 to address 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.
Criticism of American policy
Carter began his first year out of office with a pledge not to critique the new Reagan administration. He spoke out after the assassination attempt on Reagan, and voiced his agreement with Reagan on building neutron arms in the wake of the Soviet invasion of Afghanistan. He later disagreed with Reagan's handling of the Middle East. The following year, Carter called for bipartisanship to fix American economic issues, and criticized the Reagan administration's handling of the Sabra and Shatila massacre. Carter responded favorably to Reagan choosing to remain within the Camp David agreement, with distaste toward what he felt was Reagan blaming his tenure for continued difficulties in policy. In 1983, Carter judged the Reagan campaign with having falsified simplicity in solving issues, and criticized Reagan for a lack of attention to human rights violations. In 1984, Carter stated he had been wrongly presented as weak by Reagan due to a commitment to human rights during the previous presidential election, and condemned Reagan for not making rescue efforts to retrieve four American businessmen from West Beirut. In 1985, Carter rebuked Reagan over his handling of peace within the Middle East, his support of the Strategic Defense Initiative, and Reagan's claim of an international conspiracy on terrorism. Carter's insistence that Reagan was not preserving peace in the Middle East continued in 1987, Carter during the year also criticizing Reagan for adhering to terrorist demands, nomination of Robert Bork for the Supreme Court, and handling of the Persian Gulf.
During the presidency of George W. Bush, Carter stated his opposition to the Iraq War, and what he considered an attempt on the part of Bush and Tony Blair to oust 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, and later stated he was just comparing Bush's tenure to that of Richard Nixon. Carter's comments received a response from the Bush administration in the form of Tony Fratto saying Carter was increasing his irrelevance with his commentary. By the end of Bush's second term, Carter considered Bush's tenure disappointing, which he disclosed in comments to Forward Magazine of Syria.
Though he praised President Obama in the early part of his tenure, Carter stated his disagreements with the use of drone strikes against suspected terrorists, Obama's choice to keep Guantanamo Bay detention camp open, and the current federal surveillance programs as disclosed by Edward Snowden indicating that "America has no functioning democracy at this moment."
During the Trump presidency, Carter spoke favorably of the chance for immigration reform through Congress, and criticized Trump for his handling of the U.S. national anthem protests.
Carter was considered a potential candidate in the 1984 presidential election, but did not run and instead endorsed Walter Mondale for the Democratic nomination. After Mondale secured the nomination, Carter critiqued the Reagan campaign, spoke at the 1984 Democratic National Convention, and advised Mondale. Following the election, in which President Reagan defeated Mondale, Carter stated the loss was predictable due to the latter's platform that included raising taxes.
In the 1988 presidential election cycle, Carter ruled himself out as a candidate once more and predicted Vice President George H. W. Bush as the Republican nominee in the general election. Carter foresaw unity at the 1988 Democratic National Convention, where he delivered an address. Following the election, a failed attempt by the Democrats in regaining the White House, Carter said Bush would have a more difficult presidency than Reagan due to not having the same level of popularity.
During the 1992 presidential election, Carter met with Massachusetts Senator Paul Tsongas who sought out his advice. Carter spoke favorably of former Governor of Arkansas Bill Clinton, and criticized Ross Perot. As the primary concluded, Carter spoke of the need for the 1992 Democratic National Convention to address certain issues not focused on in the past, and campaigned for Clinton after he became the Democratic nominee in the general election, publicly stating his expectation to be consulted during the latter's presidency.
Carter endorsed Vice President Al Gore days before the 2000 presidential election, and in the years following voiced his opinion that the election was won by Gore, despite the Supreme Court handing the election to Bush in the controversial Bush v. Gore ruling.
In the 2004 election cycle, Carter endorsed John Kerry and spoke at the 2004 Democratic National Convention. Carter also voiced concerns of another voting mishap in the state of Florida.
Amid the Democratic presidential primary in 2008, Carter was speculated to endorse Senator Barack Obama over his main primary rival Hillary Clinton amid his speaking favorably of the candidate, as well as remarks from the Carter family that showed their support for Obama. Carter also commented on Clinton ending her bid when superdelegates voted after the June 3 primary. Leading up to the general election, Carter criticized John McCain, who responded to Carter's comments, and warned Obama against selecting Clinton as his running mate.
Carter endorsed Republican Mitt Romney for the Republican nomination during the primary season of the 2012 election cycle, though he clarified his backing of Romney was due to him considering the former Massachusetts governor the candidate that could best assure a victory for President Obama. Carter delivered a videotape address at the 2012 Democratic National Convention.
Carter was critical of Republican presidential candidate Donald Trump shortly after the latter entered the primary and predicted he would lose, noting the differing circumstances of the political climate from when he was still an active politician. As the primary continued, Carter stated he would prefer Trump over his main rival Ted Cruz, though rebuked the Trump campaign in remarks during the primary, and in his address to the 2016 Democratic National Convention. In the Democratic primary, Carter voted for Senator Bernie Sanders, and in the general election, voted for Hillary Clinton.
In October 2017, however, Carter defended President Trump in an interview with The New York Times, criticizing the media's coverage of him. "I think the media have been harder on Trump than any other president certainly that I've known about," Carter stated. "I think they feel free to claim that Trump is mentally deranged and everything else without hesitation." He further stated that he did not believe that Russia was involved in changing votes during the presidential election or primaries. "I don't think there's any evidence that what the Russians did changed enough votes, or any votes," he told the Times. He also praised Trump for reaching out to Saudi Arabia and stated that the President has been under a stricter spotlight than his predecessors. After the interview, Trump himself praised Carter's comments and thanked him over , writing "Just read the nice remarks by President Jimmy Carter about me and how badly I am treated by the press (Fake News). Thank you Mr. President!"
Carter criticized the Bush administration's handling of Hurricane Katrina, 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, in addition to writing op-eds about the goodness seen in Americans who assist each other during natural disasters.
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 and Gerald Ford, and Theodore Hesburgh.
Carter serves as an Honorary Chair for the World Justice Project, and formerly served as one on the Continuity of Government Commission from 2003 to 2011. He continues to occasionally teach Sunday school at Maranatha Baptist Church.