He was educated at Tel Aviv University and Street Antony"s College, Oxford from which he received a Doctorate.Phil.
In history. Ben-Ami speaks fluent Hebrew, Spanish, French and English. He was a historian at Tel Aviv University from the mid-1970s, serving as head of the School of History from 1982 to 1986. His initial field of study was Spanish history, and his 1983 biography of the former Spanish Dictator, General Primo de Rivera (1923–1930), is recognized as the most authoritative study on this subject.
He later turned his attention to the history of Israel and the Middle East, leaving a legacy of expertise in Spanish inter-war year politics.
From 1982 until 1986, before he entered politics, he was the Israeli ambassador to Spain. In 1996 he was elected to the Knesset on Labour"s list.
When the One Israel-led government of Ehud Barak took office in July 1999, Ben-Ami became the Minister of Internal Security, responsible for the Israel Police. In August 2000, when David Levy resigned as Foreign Minister during talks with Palestinian leaders in the United States, Barak designated Ben-Ami to be the acting Foreign Minister and he was officially appointed to the role in November 2000.
Ben-Ami refused to serve in the Sharon government and resigned from the Knesset in August 2002.
In their report published in 2003, the Or Commission held him responsible for the behavior of security forces during the October 2000 riots in which Israeli police killed 12 Israeli Arabs and one Palestinian, and failed to predict and control rioting which resulted in the death of a Jewish Israeli. The report recommended that Ben-Ami be disqualified from serving as Internal Security Minister in the future. Ben-Ami is currently Vice-President of the Toledo International Centre for Peace (TICpax), which, according to its mission statement, "seeks to contribute to the prevention and resolution of violent or potentially violent international or intranational conflicts and to the consolidation of peace, within a framework of respect and promotion of Human Rights and democratic values."
His latest book is Scars of War, Wounds of Peace: The Israeli–Arab Tragedy (Oxford, 2006) challenges many of the founding myths in Israel"s modern history especially related to the war of independence.
He currently serves as vice president of the Toledo International Centre for Peace.
Despite the disqualification, Ben-Ami was not considered to be a hard-liner in Israeli relations with the Palestinians and during his time in the Barak government, he was a political rival of Shimon Peres. Ben-Ami backed the Meretz party for the 2009 Knesset elections.