The Kargil conflict represents a landmark event in international nuclear history. Apart from the Sino-Soviet border clash of 1969, it is the only direct conflict between two states armed with nuclear weapons. Kargil also was the first overt conflict between India and Pakistan since the 1971 war established the state of Bangladesh and since both states openly demonstrated their nuclear capabilities in 1998. The Kargil conflict tested long-held assumptions regarding nuclear stability, deterrence, and the consequences of nuclear proliferation. It also provides important demonstrations of intelligence failure, the operation of the stability–instability paradox, and fundamental misperceptions regarding the intentions and capabilities of well-known adversaries.

The key issue this essay analyzes is how the existence of nuclear forces affected the course of the Kargil conflict. Although nuclear weapons were not actually deployed in 1999, and although previous Indo-Pakistani crises had taken place under the shadow of emerging nuclear capabilities, the nuclear context of Kargil had three unprecedented effects on the strategic behavior of India, Pakistan, and outside parties, especially the United States. First, the achievement of mutual nuclear deterrence emboldened Pakistani military leaders to take assertive military action in Kashmir. Second, Indian elites believed that the nuclear revolution fundamentally changed Indo-Pakistani relations, and thus reacted in a slow and confused manner to the infiltration. As Pakistan's military role became apparent, India responded with unexpected vigor, both militarily and rhetorically.