An operational nuclear-weapon capability needs many types of component, including bases, communications, control systems and trained personnel. Its core however comprises nuclear weapons and systems for delivering them.
Weapons
Like all the five nuclear-weapon states recognised by the Nuclear Non-Proliferation Treaty (NPT), at least in the earlier days of their capability, India and Pakistan have provided little official information about the number or characteristics of their nuclear weapons. Both however made statements about the number and yield of their test explosions in May 1998. India announced five tests, the biggest with a yield of 43 kilotons; Pakistan announced six, the biggest with a yield of 25 kilotons. External experts, using seismological data, questioned whether the yields were as high as claimed, and a distinguished Indian nuclear scientist later urged further testing as necessary to consolidate assured thermonuclear capability. There is however no doubt that both countries have proven designs capable of at least the yields of the bombs used in 1945 against Hiroshima and Nagasaki.
Both governments have had to consider whether, for confidence and deterrent credibility, they needed further testing badly enough to warrant incurring the international political costs of again breaching the long de facto global moratorium on tests. Both have said that they do not need this, though they are not bound by treaty and have not permanently renounced the option.
Neither country has given any indication of how many weapons it has or plans to have. External speculations, based mostly on estimates (also conjectural) of present or prospective stocks of materials like plutonium and highly-enriched uranium, vary widely. Typical guesses impute about a hundred weapons currently to India and fifty to Pakistan, with capabilities within the next few years to reach, if desired, the high and low hundreds respectively.
Nothing specific has been said officially by either country about the scale of their eventual requirement. In strategic logic, that would need to reflect the doctrine chosen in such respects as the nature of targeting and whether there should be potential to ride out a hostile first strike, to mount more than one level of strike, and to deal with one adversary while maintaining deterrence of others. [Doctrine will be discussed in a separate briefing note.] Unofficial commentators in India have suggested figures in the range 150-500; no comparable suggestions have been voiced in Pakistan. The smallest declared holding among the five NPT-recognised nuclear powers is the United Kingdom's 200.
Delivery Vehicles
Delivery vehicles can be either aircraft or missiles. Missiles can be land-based, in fixed emplacements or on mobile launchers, or sea-based on surface ships or submarines. All types of vehicle have advantages and disadvantages needing to be weighed in the particular circumstances of South Asia. Aircraft are versatile and recallable but vulnerable on the ground and in the air. Missiles (usually ballistic ones) are more certain to reach their targets, but vulnerable if in fixed sites and posing greater problems of command and control if on mobile launchers, whether land- or sea-based. Costs are also a major factor, and submarines are especially expensive.
For delivering nuclear weapons both countries would at present have to rely heavily on fighter/ground-attack aircraft. These need special adaptation for the role, and neither country has said how many or which types in their holdings are so adapted.
India has nearly 500 F/GA aircraft. The Jaguar has the longest range, but is an elderly design and not the most probable candidate. The more likely preferred choice is the Mirage 2000, with a radius of action of 600 kms for a typical unrefuelled operational flight profile; this could cover from Indian bases all major cities in Pakistan, but would give no strategic capability against China. Pakistan has about 110 F/GA aircraft, the farthest-reaching being the F-16; its typical radius of action, at 1,200 kms, would cover Delhi and Mumbai but not Southern or Eastern India.
Both countries seek increasingly to concentrate capability on land-based ballistic missiles. They have tested systems of varying range up to, for India, the 2,000-km. Agni-2 system and, for Pakistan, the 1,500-km Ghauri system; small numbers of the latter are already in service. India (which has the more demanding operational requirement, given that it seeks a deterrent posture in relation to China) plans to test soon a 3,000-km. Agni-3 system. Ranges like those of the Agni and Ghauri systems plainly imply nuclear delivery, and so do those of most other ballistic missile systems held in or tested for the two armouries, but there is ambiguity about India's intentions for the 150-km. Prithvi I system reportedly based near Pakistan's eastern frontier.
Neither country possesses sea-based nuclear delivery systems or has them in early prospect. India has tested a conventionally-armed cruise missile for use from surface ships, but this would be ill-suited for the nuclear role. A wide-ranging report on Indian nuclear doctrine by a distinguished government-commissioned advisory group in August 1999 envisaged an eventual triad (aircraft, land-based missiles, sea-based missiles) such as the United States and Russia possess, but the Indian government did not endorse the report. Some Indian commentators have argued that in the long term India should concentrate its resources on submarine-launched ballistic missiles; it would however take many years and heavy expenditure to implement that. There is no evidence that Pakistan is likely to pursue sea-based options.
