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During Prime Minister Manmohan Singh's visit to the United States, he appeared to reverse India's decades-long refusal to join the Nuclear Non-Proliferation Treaty (NPT). On Fareed Zakaria's GPS show on November 29, Singh responded to a question by indicating that India would be willing to join the NPT as a nuclear weapons state. No Indian leader has ever publicly expressed willingness to accept the NPT.

The prime minister also suggested that India would welcome a US effort to help it become a nuclear weapons state under the NPT. If India intends to follow through on the prime minister's expression of NPT interest, this transformation will have significant implications for India as an emerging geopolitical actor and for nuclear diplomacy, including President Barack...