 Among other conflicts, he covered the 1967 Six-Day War in Israel, the war in Vietnam (six trips), the conflict in Northern Ireland, and the Biafran war for independence from Nigeria.Lewis also travelled to Rhodesia to cover that country's efforts to survive a United Nations economic boycott.Lewis' interviews with Rhodesian Prime Minister Ian Smith in the late 1960s are widely credited with bringing that issue to public attention in the U.S. Lewis argued that the boycott was instigated because Rhodesia had not perfected a "one-man, one-vote" system of government.