Subrahmanyam was born on 19 January 1929 and grew up in Tiruchirapalli and Madras.
On 11 November 2005, speaking on the 40th anniversary of IDSA's founding, Prime Minister Manmohan Singh singled out Subrahmanyam for his achievements: Subrahmanyam's incisive writings continue to stimulate and contribute to the thinking of strategic analysis and policy makers in this vital area of national concern.