Jimmy Carter wasn’t just the best former president. He was the most successful | Peter G Bourne

Jimmy Carter has died. He is sometimes referred to, especially by Republican critics, as America’s best former president – implying that his time in the White House was, by contrast, a failure. In fact, he was by most measures a highly successful one-term president, getting more done in four years than most presidents accomplish in twice the time.

It is true that his post-presidency accomplishments were unprecedented – a fact attested to by, among other things, his receipt of the 2002 Nobel peace prize for “his decades of untiring effort to find peaceful solutions to international conflicts, to advance democracy and human rights, and to promote economic and social development”.

I worked for Carter and counted him as a friend of many years; I saw first-hand his commitment to the values honored by the Nobel committee.

As evidenced by his campaign promise – “I will never lie to you” – Carter ran for president with the explicit intent of restoring moral leadership to the White House. One of his first acts as president, in 1977, was to issue a blanket amnesty to those who broke the law in their opposition to the Vietnam war. That powerful and politically brave gesture was a step toward healing a country that was polarized in so many ways during the Johnson and Nixon years.

Carter came into office determined to improve the management and efficiency of the federal government. In his first two years he got a broad legislative program through Congress. He also transformed the job of vice-president, giving Walter Mondale an office in the West Wing and involving him in policy decisions; this elevated role for vice-presidents has been adopted by every subsequent president.

Carter created new federal Departments of Education and Energy. He was the first president to emphasize the importance of renewable energy and, in a powerful symbolic act, he had solar panels installed on the roof of the White House.

Although previous administrations had appointed a small number of African Americans and women as tokens, Carter made it a priority to recruit Black people and women, including civil rights and feminist leaders.

It was, however, in foreign policy that Carter had his greatest impact. Richard Nixon and Henry Kissinger had created the opening with China, but it was Carter who normalized US-China relations. US control of the Panama Canal had long been a source of resentment and hostility throughout Latin America, stirring widespread political unrest; Carter returned control of the canal to the Panamanians and defused the boiling anti-US sentiment. Carter negotiated the Salt-II disarmament treaty with the Soviets (although it was not ratified by the Senate).

But Carter’s greatest foreign policy achievement was his negotiation of the Camp David accords, which have not been violated in more than 40 years and finally brought peace between Egypt and Israel.

Despite his accomplishments, Carter was defeated for re-election. A primary challenge by Ted Kennedy split the Democratic party. Southern white people felt Carter had betrayed them on race. Conservatives felt he had “given away” the Panama Canal. And his failure to use massive military force against Iran over the 444-day hostage crisis at the US embassy made him seem weak in the eyes of many Americans. But Carter knew that any military action would almost certainly result in the death of the 52 American hostages. Eventually they all came home unharmed.

Carter was 56 when he left the White House: too young to retire. Given his temperament and his intense Christian belief, it was only natural he find a worthy cause to fill his time. He established the Carter Presidential Center. It was broadly focused on peace. He and the first lady, Rosalynn Carter, traveled to more than 100 countries dealing with conflict resolution and election monitoring. The involvement of the Carter Center rapidly became the sought-after “gold standard” for elections all over the world.

He worked with several African countries to increase agricultural production with genetically selected seeds, fertilizer and special planting techniques. In 1985, he launched a campaign to eradicate a parasitic disease, guinea worm, that afflicted millions across Africa and parts of Asia. As a result, last year, there were fewer than 20 cases. He also worked to reduce other devastating diseases, including river blindness and trachoma, and was an enthusiastic supporter of Habitat for Humanity. Somewhere he also found the time to write 20 books, mostly autobiographical, but including a novel and an anthology of his poetry.

Carter was deeply religious; his faith, more than anything, animated him. Although evangelical, he did not join other American evangelicals’ embrace of rightwing politics. “If I had not been born a Baptist,” he once told me, “I would probably have become a Mennonite.” (One of the historic Protestant “peace churches” dating from the 1500s, the Mennonite church believes a Christian’s values must be manifest in all aspects of daily life. Mennonites are strict pacifists.) He was also a longtime disciple of the pragmatic theologian Reinhold Niebuhr.

At age 95, Carter still taught Sunday school in the small Georgia town where he grew up. Every week, hundreds, sometimes as many as a thousand, came from across America and the world to hear his homilies. The following he enjoyed 40 years after he left the White House suggests that his greatest legacy may be the moral values his life exemplified.

• Peter G Bourne served in the Carter White House as special assistant to the president. He is the author of Jimmy Carter: A Comprehensive Biography from Plains to Post-Presidency and a visiting senior research fellow at Green Templeton College, University of Oxford