India has won a significant victory in its efforts to claim an exception to rules designed to thwart the proliferation of nuclear weapons. Delhi did not accomplish this on its own: It got considerable help from Washington, which seeks to build a new relationship with the world's largest democracy.

However, strategic gains may have come at the expense of the global nonproliferation order. The Indian exception will encourage other countries to seek similar treatment, which will accelerate the unraveling of the Nuclear Nonproliferation Treaty (NPT).

India, like Pakistan and Israel, has long objected to the NPT, arguing that the treaty's distinction between nuclear and nonnuclear weapons states is a form of discrimination. Delhi never signed the treaty and has remained committed to the development of its own nuclear arsenal, for reasons of national defense and international status. It tested its first "peaceful nuclear explosion" in 1974 and weapons-related devices in 1998.