It will lead to a renewed drive behind the Indian government's plans to build and deploy nuclear weapons. Pakistan, which has always sought to match its larger neighbor and maintain parity, will also be pulled into this nuclear competition. Pakistan, too, has rejected the NPT for its unequal obligations. However, Pakistan's security interests are inextricably tied to India's military posture. The overall outcome will be an increasing salience of nuclear weapons in South Asia, which will not only come as a blow to regional arms control initiatives, but also serve as an incentive for other potential proliferators to follow suit.
China is thus likely to invest in a more robust nuclear triad.
A US NMD could also force changes in China's deployment posture. China currently lacks the technical capability to maintain its nuclear force on a high-alert status. Warheads are stored separately from their missile launchers. Because Chinese missiles are liquid-fueled, they require lengthy launch preparations. China's current nuclear modernization plans will bring it within striking distance of deploying a credible and survivable deterrent.