Subrahmanyam was a key figure in framing and influencing Indian security, nuclear policy and in advocating Indian nuclear positions on the global stage, both as a policy wonk and as a journalist. He was the second director of the New Delhi-based Institute for Defence Studies and Analyses. He is also noted for having steered several Indian government committees and commissions of inquiry, including the Kargil Review Committee after the Kargil War. Subrahmanyam was a major advocate of the 2007 Indo-US civilian nuclear agreement, adding some heft to the Manmohan Singh government's championing of the deal in the face of much opposition.