Why did India merely flirt with nuclear weapons in the 1960s and 1970s only to emerge as a nuclear power in the 1990s? Although a variety of factors informed India’s prolonged restraint and subsequent breakthrough, new evidence indicates that India’s “nuclear odyssey” can be understood as a function of Indian leaders’ ability to secure their country through nonmilitary means, particularly implicit nuclear umbrellas and international institutions. In the 1960s and 1970s, India was relatively successful in this regard as it sought and received implicit support from the superpowers against China. This success, in turn, made acquiring the bomb a less pressing question. At the end of the Cold War, however, nonmilitary measures ceased to be viable for India. In the late 1980s, waning Soviet support and the failure of Rajiv Gandhi’s diplomatic initiatives led to the creation of India’s de facto nuclear arsenal. In the 1990s, India developed a more overt capability, not simply because the pro-bomb Bharatiya Janata Party came to power, but also because its external backing had vanished and because its efforts to improve its security through diplomacy proved unsuccessful.