Educated at St Austell Grammar School, Christ's College, Cambridge and Yale University, Martin joined the Royal Air Force as a Flying Officer in 1948. He became Dean of the Faculty of Social Sciences at the University of Wales in 1966.
He was appointed Professor of War Studies at King's College, London in 1968, Vice-Chancellor of Newcastle University in 1978 and Director of the Royal Institute of International Affairs in 1991. In 1981 he gave the Reith Lectures on the theme The Two-Edged Sword. He was appointed Deputy Lieutenant of Tyne and Wear in 1987.
- Considerations affecting an extension of the test ban, 1966