In South Asia, an unprecedented nuclear build-up is underway and gaining momentum spurred by Pakistan’s break-neck effort to double its already sizable arsenal over the next decade (rising from 125 weapons today to 250-350 over the next 5-10 years). India is playing serious catch-up with new land-based rockets and a new strategic submarine in its mix of delivery systems after a decade of sluggish growth (its current small arsenal of 25 weapons will increase to 100 over the next 5-10 years).

Pakistan has the fastest growing nuclear weapons program in the world, according to U.S. officials cited by a leading American nuclear expert, David Albright. With 120-130 thousand people directly involved in its nuclear weapons production and nuclear-armed missile program, Pakistan is completing construction on two new plutonium reactors (less than 100 miles from the scene of fighting between the Army and the Taliban) and building other infrastructure.

Pakistan does not officially reveal the cost of its secret nuclear program. In 2009, a credible assessment by a investigative journalist with expertise in the subject provided information on which we can calculate the overall nuclear program budget (weapons and missile delivery systems) to be approximately $781 million — $300 million for the Pakistan Atomic Energy Commission and $481 million for the strategic missile delivery system. This sum represents 10 percent of Pakistan’s annual defense budget ($7.9 billion). Independently, an American expert on the Pakistani nuclear program suggested that Pakistan spends up to 10 percent of its defense budget on nuclear forces. This report assumes that the current budget pressure on the Pakistani program is containing cost growth in 2011; core and full costs are estimated at $800 million and $2 billion, respectively. The health and environmental consequences of Pakistan’s recent expansion of its infrastructure constitute a significant cost which can be expected to grow rapidly as new plutonium factories come on line. Furthermore, core spending on the nuclear program is likely to grow significantly for the rest of the decade as Pakistan undertakes a rapid build-up, perhaps by two- or three-fold, of its arsenal.

India’s nuclear program is largely keyed to China’s and to a lesser extent to Pakistan’s, and both of India’s nuclear rivals are expanding their arsenals sufficiently to stimulate India’s program. India has always minimized the role of nuclear weapons in its national security strategy, and consequently was slow to acquire an arsenal and restrained in the size of the arsenal it built. The impetus to expand the arsenal is stronger today, however. India’s modernization program already has considerable momentum yielding as much as a four-fold increase in the Indian arsenal over the next decade.

India, like Pakistan, keeps its nuclear budget under wraps. Very few details are publicly known about the program, and its cost is rarely discussed in public. One published estimate contends that the Indian program, very conservatively estimated, costs 0.5 percent of annual GDP. Using $1.538 trillion dollars as the GDP of India, this would mean that India spends about $7.7 billion on nuclear weapons at purchasing power parity exchange rates. This would represent 22 percent of India’s overall defense budget, a proportion that exceeds Pakistan’s ratio of nuclear to overall spending by a factor of two, and China’s ratio by a factor of four.

This report assumes that India’s nuclear spending does not exceed 10 percent of its overall military spending, a fraction in line with current Pakistani allocations. India’s nuclear budget would thus be about $3.8 for core costs, which is about 60 percent of China’s nuclear budget. We estimate the full cost to be $4.9 billion.