As he prepared to leave Washington on Wednesday night after a visit that exceeded all expectations, Prime Minister Manmohan Singh called in his delegation to commend all those who had worked behind the nuclear pact with the United States.

That gesture from Singh, on the eve of his return via a brief halt in Switzerland, recognised at once the historic nature of the pact and the intensity of the negotiations with the Bush Administration and within the Indian system itself.

Anil Kakodkar, the head of the Atomic Energy establishment, who brought in much-needed technical clarity to the Indian negotiating position, held the key to achieving the twin objectives—sustaining India’s nuclear arsenal and acquiring civilian nuclear technology.

But there were five other men, who had to handle the complex political and diplomatic dimensions of India’s nuclear policy and contributed to the talks which went right down to the wire.

The stellar role in the nuclear talks was reserved for External Affairs Minister K Natwar Singh, who is not new to arms control. Under Rajiv Gandhi in the late 1980s, he played a key role in pushing the multilateral Chemical Weapons Convention. However, it was his sense of the rare moment at hand and the authority to bring the talks to a close, as they swung wildly between a historic outcome and a diplomatic disaster, which counted in the end.

Natwar Singh’s excellent personal chemistry with US Secretary of State Condoleezza Rice provided a solid foundation to let the talks continue even though differences seemed irreconcilable. His meeting with President Bush in April produced the promise at the highest political level that the US is interested in promoting nuclear energy development in India.

While Natwar Singh secured the political commitment on nuclear energy cooperation, it was the responsibility of Ronnen Sen, the Indian Ambassador to the US, to translate it into credible action.

Sen’s long association with India’s nuclear and space programmes is not widely known. When in a top secret decision, Rajiv Gandhi exercised the nuclear weapon option in the late 1980s, Sen, then his foreign policy aide, provided the vital link between the PM and the Department of Atomic Energy.

Sen was also associated with the decision to purchase nuclear reactors from Russia in 1988. As ambassador to Moscow in the 1990s, Sen ensured the transfer of Russian cryogenic engines for India’s space programme after the collapse of the Soviet Union in 1991 and protected a variety of other sensitive projects with Moscow.

When he was appointed ambassador to Washington last year, Sen was determined to resolve the nuclear differences with the US. If Sen managed the American end, it was Foreign Secretary Shyam Saran who had the task of bringing coherence to the Indian negotiating position and steering it to a successful conclusion.

Saran, who was the then Prime Minister P V Narasimha Rao’s main foreign policy aide, played a key role in nurturing India’s nuclear option at one of the most vulnerable moments in history and opened up the possibility of nuclear testing in 1995. Although he was not directly involved in earlier nuclear diplomacy, National Security Advisor, M K Narayanan, brought in a measure of skepticism to negotiations which made sure no potentially troublesome dimension was neglected.

While the Prime Minister thanked all the big guns involved in the nuclear talks, he did not forget S Jaishankar, Joint Secretary (Americas) in the Ministry of External Affairs.

Jaishankar, who holds a doctorate on nuclear diplomacy, was involved in the mid 1980s in the first negotiations with the US on high tech transfers under Indira Gandhi and Rajiv. When all is said and done, it is the joint secretary who manages the paper work—the quality of which defines the potential for success or failure.