Securing Pakistan’s Nuclear Weapons Complex

by David Albright

October 25, 2001

Paper 1commissioned and sponsored by the Stanley Foundation for the 42nd Strategy for Peace Conference, Strategies for Regional Security (South Asia Working Group), October 25-27, 2001, Airlie Conference Center, Warrenton, Virginia

During times of relative political and social normalcy, the security of Pakistan’s nuclear arsenal is probably adequate and could be expected to improve consistent with other nuclear programs worldwide. However, fallout from Pakistan’s decision to cooperate with the United States following the September 11th terrorist attacks may severely test Pakistan’s security system throughout its nuclear weapons complex. Instability in Pakistan could make its nuclear weapons and stocks of nuclear explosive material dangerously vulnerable to theft. If domestic instability leads to the downfall of the current Pakistani government, nuclear weapons and the means to make them could fall into the hands of a government hostile to the United States and its allies.

The precise threat to Pakistan’s stability or its nuclear weapons complex is difficult to judge. Pakistan’s Foreign Ministry says that “our [nuclear] assets are 100 percent secure, under multiple custody.”2 President General Pervez Musharraf said “there is no question of [Pakistan’s nuclear assets] falling into the hands of any fundamentalists.”3 However, these statements are untested and spark skepticism, particularly in the changed security environment following September 11th.

Pakistan is believed to maintain tight control over its nuclear assets, and it may have instituted special steps to deal with the current situation. Nonetheless, the U.S. government and the international community should work to improve security over Pakistan’s nuclear assets, both in the short and long term.

The war on terrorism is expected to be long and drawn out. The Pakistani military and intelligence services may retain strong ties to Taliban officials in Afghanistan. Like the Pakistani population, many among the Pakistani military or the nuclear establishment could be sympathetic to fundamentalist causes or hostile to the United States. These sympathies could grow, depending on the course of the war in Afghanistan or elsewhere. Such insider threats could pose one of the most vexing problems in the current crisis.

But even before the current crisis, Pakistan likely would have benefited from improved physical protection of its military and civilian nuclear facilities. According to a former Clinton administration Energy Department official, before September 11 Pakistan had requested some kind of assistance to improve its physical security capabilities. 4

In addition, significant security lapses and weaknesses have occurred in many nuclear weapons programs. A frequently quoted rule-of-thumb is that security needs to constantly improve in order to stay one step ahead of would-be thieves.

The United States struggled through much of the 1970s and 1980s to develop a security system to adequately protect its nuclear weapons and weapons components. Yet, it still encounters difficulty in allocating enough resources to protect its nuclear weapons complex adequately.

The former Soviet Union experienced a severe drop in the effectiveness of its nuclear security systems in the early 1990s. Russia, with the help of the United States and other countries, is now engaged in a massive effort to improve the security of its nuclear materials and weapons.

Providing assistance to Pakistan, however, is not as straightforward as aiding the former Soviet Union. Direct, substantial assistance could embarrass the Pakistani government and provide ammunition to the government’s political opponents that the United States is attempting to gain direct control over Pakistan’s nuclear weapons. In addition, Pakistan treats the location of its nuclear weapons as highly classified and apparently depends on this secrecy to increase the survivability of its nuclear weapons. Pakistan is unlikely to welcome U.S. assistance that could reveal its nuclear weapons storage sites.

In addition, the United States faces a series of constraints that complicate the provision of assistance to Pakistan. Such assistance should not violate U.S. commitments or objectives under the Nuclear Non-Proliferation Treaty (NPT), harm U.S. relations with India, inadvertently encourage nuclear testing or otherwise contribute to advances in Pakistan’s nuclear arsenal, or increase the threat of a nuclear exchange between India and Pakistan.

Pakistan’s Nuclear Weapons Complex

During the last 25 years, Pakistan has developed an extensive nuclear weapons complex. Prior to its nuclear tests in May 1998, successive Pakistani governments tried to hide many aspects of its nuclear weapons program while simultaneously revealing enough to convince India and the rest of the world that it had workable nuclear weapons.

A result of this opaqueness is that Pakistan has released little information to the public about its complex of facilities devoted to making nuclear weapons. Typically, these activities include research, development, and testing of nuclear weapons, the production of plutonium and highly enriched uranium (HEU), the manufacture of nuclear weapons, and facilities for mating nuclear weapons to delivery systems, including aircraft and ballistic missiles.

Despite the shortage of official information, a rough sketch of Pakistan’s nuclear weapons complex can be drawn. 5 For the purposes of this report, a partial summary follows that is focused on facilities with sensitive material. These facilities would be expected to be the major focus of any attempt to improve Pakistan’s security over its nuclear weapons.

Significant holes exist in this sketch. An important missing piece is reliable information that could provide insight into the adequacy of security at critical nuclear sites or over fissile materials and nuclear weapons.

Quick Tour

All nuclear weapons complexes are composed of a myriad of facilities. They are linked together to function as a unit through transports of materials and manufactured items, personnel, and communication systems. A central, competent leadership is critical to maintaining adequate security over the complex and ensuring that adequate control exists over the nuclear weapons themselves.

Fissile Material Production. Pakistan has the capability to make both plutonium and highly enriched uranium (HEU), or “fissile materials,” for nuclear weapons. Its main uranium enrichment facilities are at the A.Q. Khan Research Laboratories at Kahuta. Pakistan also has another newer enrichment facility near Wah that the U.S. government calls the Gadwal uranium enrichment plant. It may have other production-scale facilities. Pakistan also operates smaller enrichment facilities, including the Sihala and Golra ultracentrifuge plants.

Most of these sites would be expected to have HEU and low enriched uranium (LEU) stocks. The physical security arrangements at these facilities are unknown, although these arrangements would be expected to be rigorous.

Pakistan possesses a capability to make weapon-grade plutonium for nuclear weaponsPakistan operates the Khushab reactorwhich is estimated to generate about 50 megawatts of powerlarge enough to produce plutonium for a few nuclear weapons per year.  Separation of the plutonium is reported to occur at New Labs at Rawalpindilocated near Islamabad.  This plantnext to the Pakistan Institute of Nuclear Science and Technology (Pinstech), is large enough to handle all the irradiated fuel from the Khushab reactor.  The storage arrangements for the separated plutonium are unknownalthough they would likely include vaults and other security procedures.</p><p
As of the end of 1999, ISIS assesses that Pakistan possessed 585 - 800 kilograms of weapon-grade HEU and 1.7 - 13 kilograms of separated plutonium; these quantities are sufficient for 30-50 nuclear bombs or warheads. 6

Nuclear Weapons Manufacturing Sites. Pakistan maintains facilities to produce metallic fissile material and shape the metal into nuclear weapons components. Such facilities would have fissile material in liquid, powder, and solid forms. Other facilities produce the non-nuclear components and at least partially assemble the nuclear weapons. The location of these facilities has not been reported extensively, although at least some of these facilities are located near Wah.

Whether or not all of Pakistan’s nuclear explosive material has been converted to nuclear weapons is unknown. One would expect that relatively large quantities of HEU are not in the form of partially assembled nuclear weapons and would be in-process in nuclear fuel cycle facilities. This amount translated into nuclear weapon equivalents must be subtracted from the above estimate of 30-50 nuclear weapons.

Nuclear Weapons Storage and Deployment Sites. Pakistan is widely reported not to have deployed its nuclear weapons. What that means exactly is difficult to determine from the available literature. For example, a definition of deployment is that the weapons have been transferred to military units for storage and rapid mating with delivery systems at military bases. Under this definition, South Africa did not deploy its nuclear weapons. However, the situation in Pakistan may be murky and may in fact best be described as partial deployment.

Pakistan is reported to have several nuclear weapons storage facilities. Their exact locations are unknown. Reports and interviews with knowledgeable individuals mention that storage sites are on military bases. However, other storage locations, such as tunnels or mines, would be expected.

According to a variety of media reports, Pakistan’s nuclear weapons are implosion-type designs and are stored with their fissile cores separated from the non-nuclear components. 7 This arrangement may reflect safety limitations in the weapons, rather than be a fundamental method to provide better access control over the weapons as in the case of South Africa. Pretoria designed its weapons to have front and back sections that were stored separately.

The simplest interpretation of the available information is that the fissile core and the rest of the device are stored separately in vaults. However, it is also possible that the weapon minus the fissile core is mounted on a delivery vehicle, and the fissile core is stored separately.

Pakistan’s nuclear weapons are not thought to be “one-point safe” or equipped with permissive action links (PALs), at least as defined by the United States. 8 PALs are often viewed broadly as devices to prevent the unauthorized use of a nuclear weapon. The more effective ones, however, are integral to the warhead and require the entry of a code before the weapon can be armed and fired. A box and a lock could under some definitions be called a PAL. The problem, however, is that such a system is not integral to the weapon, and should be more appropriately considered as a physical protection device rather than a PAL. Similarly, a system applied after the weapon is built, such as a control over the electronic firing systems, could also be bypassed in a straightforward manner. Here, PALs are thus defined narrowly as a system incorporated in the design of the weapon that prevents unauthorized access.

It is unknown if Pakistan has coded switch devices integral to its delivery systems (as opposed to the actual warheads). Such switches would act as hardware “gatekeepers” for ballistic missiles or aircraft. The need for a special code to arm and fire the missile or drop a gravity bomb would impede the ability of unauthorized personnel to carry out a nuclear strike. Such devices may be easier to master than PALs.

Pakistan appears to emphasize the need to keep its storage locations secret. This strategy is different from the situation in the United States and Russia, where nuclear storage sites are relatively distinctive because of the elaborate security arrangements. These sites have extensive security, including fences, towers, guards, and bunkers, that is visible in overhead surveillance.

Development and Testing of Nuclear Weapons. Pakistan has a range of facilities involved in the development and testing of nuclear weapons. Pakistan has repeatedly stressed its need to be a nuclear equal to India to maintain its security. Nuclear parity has been implicitly adopted by much of the Pakistani leadership as a litmus test for the credibility of its arsenal. Therefore, Pakistan may keep nuclear devices ready for rapid testing in response to any future Indian tests. Towards this end, facilities associated with development and testing of nuclear weapons may hold nuclear explosive devices or significant quantities of fissile material.

Transportation of Fissile Material and Weapons. Little is known of the transportation arrangements for sensitive nuclear items in Pakistan. The type of transport containers or vehicles, or the extent of armed escorts, is unknown. Pakistan’s transportation vehicles are unlikely to be of the caliber of the Department of Energy’s safe-secure transport (SST) vehicles.

Command and Control. Much has been written on this subject, so only a very brief summary appears warranted. The Pakistani military controls the nuclear weapons, and has instituted a range of measures to tighten controls over the nuclear weapons complex. According to a wide variety of South Asian specialists, the military is the least corrupt and most professional part of Pakistani society.


Multiple vulnerabilities exist in a nuclear weapons complex. Transportation of sensitive items is often viewed as one of the weakest links. Accordingly, many countries involved in transporting fissile material or nuclear weapons have invested heavily in better securing their transports. Insider threats are a recurring problem. The situation in the former Soviet Union highlights this threat.

Groups or individuals may violate security rules for a variety of reasons, including profit, settling a grudge, or religious or ideological motives. Violators may try to gain control over sensitive items for their own use or to transfer these items to another state or to other non-state actors.

A special concern is that Pakistan will suffer another coup. A new leadership can be expected to place a high priority on seizing the country’s nuclear assets.

The threat of theft or diversion of fissile material or nuclear weapons falls into three general areas:

    Outsider Threat–The possibility that armed individuals or groups from outside a facility gain access and steal weapons, weapons components or fissile material.

    Insider Threat–The possibility that individuals who work at a facility will remove fissile material, nuclear weapons, or weapons components without proper authorization.

    Insider/Outsider Threat–The possibility that insiders and outsiders conspire together to obtain fissile materials, weapons, or weapon components.

If Pakistan suffers extreme instability or civil war, additional threats to its strategic nuclear assets are possible:

    Loss of Central Control of Storage Facilities–Clear lines of communication and control over weapons, weapons components, and fissile material may be broken or lost entirely.

    Coup–In the most extreme case, a coup takes place and the new regime attempts to gain control of the nuclear complex. Foreign governments may intervene to prevent hostile forces from seizing the strategic nuclear assets.

In the current situation, Pakistan must also increasingly worry that experts from the nuclear complex could steal sensitive information or assist nuclear weapons programs of other countries or terrorist groups. The information could include classified nuclear weapons manufacturing data, exact storage locations of weapons or fissile material, security and access control arrangements, or operational details about the weapons.

Criteria for Providing Assistance to Pakistan

On the surface, it makes sense to provide a wide variety of assistance to increase the security of Pakistan’s nuclear weapons complex. However, many types of assistance could undermine other U.S. objectives such as bolstering nonproliferation norms or reducing the chance of nuclear war between India and Pakistan. In particular, some of the equipment the United States might provide for the purpose of nuclear security may in fact be “dual purpose,” meaning that such materials or technologies could conceivably improve Pakistan’s ability to deploy nuclear weapons operationally. This would be an unintended and unwanted consequence of U.S. efforts to secure Pakistan’s existing fissile material stockpiles and nuclear weapons.

Bruce Blair, President of the Center for Defense Information, tells of an experience he had in Russia. A senior Russian official in St. Petersburg told him that a group of Indian nuclear officials had asked for aid in making PALs for their nuclear weapons. If they could make PALs, the Indians said that they could put nuclear weapons on a higher level of readiness and assure the political leadership that the weapons were safe. Thus, a PAL could provide both greater assurance against unauthorized use of nuclear weapons and increased ability to deploy of nuclear weapons. In South Asia, deployed nuclear weapons would increase the chance that a military conflict between these two states could escalate into a nuclear exchange.

The criteria that the United States should consider in providing assistance include, but are not limited to, the following:

    Is the assistance consistent with U.S. obligations under the NPT? Under Article I of the NPT, each nuclear weapon state “undertakes … not in any way to assist, encourage, or induce any non-nuclear weapon state to manufacture, or acquire nuclear weapons or other nuclear explosive devices, or control over such weapons or explosive devices.” The administration needs to judge, both as a matter of policy and on a case-by-case basis, whether providing particular types of assistance to Pakistan, which under the NPT is a non-nuclear weapon state, constitutes a violation of this obligation or otherwise undermines the NPT. For example, assisting Pakistan to improve the security of its nuclear weapons storage facilities may be permissible. However, assistance that improves the safety and security of a nuclear warhead itself may also significantly improve Pakistan’s ability to deploy a warhead on a ballistic missile, and may be prohibited under the NPT.

    Will the assistance encourage nuclear testing by Pakistan? The type of assistance given to Pakistan could inadvertently spark Pakistan to test a nuclear device to further improve the weapons design or operational capabilities.

    Does the assistance increase the chances for nuclear war in South Asia? U.S. assistance should not permit the more rapid deployment of nuclear weapons, or make the weapons more reliable. The United States should also ensure that assistance does not allow Pakistan to store its warheads intact. The nuclear balance between India and Pakistan is not stable, and well-intentioned but short-sighted efforts to improve the safety and security of Pakistan’s nuclear arsenal could end up increasing the risk of nuclear war between India and Pakistan.

    Does the assistance negatively affect U.S. relations with India or other states? Some assistance may lead India to demand similar assistance or stimulate it to take countermeasures that may increase regional insecurity and complicate its relation with the United States.

Pakistan also faces constraints in accepting assistance:

    Does the assistance undermine the regime politically? The Pakistani government must resist assistance that could lead to charges that the United States is somehow gaining control over Pakistani nuclear weapons.

    Does the assistance reveal the location of sensitive nuclear weapon storage sites? Secrecy of the nuclear weapon storage sites is likely a key aspect of Pakistan’s nuclear strategy. Finding a proper balance between security and secrecy may be challenging. Although extensive physical security is desirable, it may also reveal the site to an enemy. Sophisticated communication equipment, designed to allow more effective control, may also be an indicator of the true purpose of the site. If the equipment came from overseas, Pakistan may also worry that it is “bugged,” revealing the location of the site to a foreign power when it is operated.

Types of Assistance

The above constraints appear to severely limit the type and assistance that can be offered to Pakistan. However, in practice, a great deal of critical assistance can be provided. Most of the assistance can be provided quickly in response to short-term needs defined by the Pakistani government. Additional assistance can be provided as part of a long-term strategy to improve security over nuclear weapons in both India and Pakistan.

U.S. assistance should be based on the guiding principle that Pakistan will continue to store its nuclear weapons in a disassembled state. This guiding principle would permit a variety of assistance that could significantly improve controls against unauthorized use of nuclear weapons.

Given the posited threats, Pakistan should be encouraged to reassess the security of its nuclear complex and make improvements where necessary. Although official statements that security is airtight may serve a necessary political purpose, they should not delude the authorities themselves into believing that the current crisis will not increase the risk of theft or diversion.

An optimal mix of assistance will necessarily rest on the extensive body of publicly available information about physical security and control of nuclear sites and nuclear weapons. This assistance can be supplemented by the provision of training and hardware. Examples of assistance are: generic physical protection and material accounting practices; theoretical exercises; unclassified military handbooks on nuclear weapons safety and security; more sophisticated vaults and access doors; portal control equipment; better surveillance equipment; advanced equipment for materials accounting; personnel reliability programs; and programs to reduce the likelihood of leaking sensitive information. In addition, aid could focus on methods that improve the security of nuclear weapons against unauthorized use through devices not intrinsic to the design of the nuclear weapon or through special operational or administrative restrictions.

Assistance could also include descriptions of security procedures and methods used by states that stored nuclear weapons in ways similar to Pakistan, or faced similar constraints in storing nuclear weapons. The early experiences of the Soviet Union and the practices of South Africa in the 1980s may be particularly relevant. 9

Excluded assistance would include nuclear weapons design information aimed at making more secure, reliable or safer nuclear weapons or devices, PALs, coded launch control devices, and environmental sensing devices. The U.S. government also would not provide assistance that required U.S. access to Pakistan’s nuclear weapon sites or unsafeguarded nuclear sites.

Under this arrangement, “lab-to-lab” programs would likely be discouraged. To be effective, these arrangements typically would require U.S. national laboratory officials to have access to sensitive Pakistani sites.

Much of the assistance could be provided relatively rapidly. However, Robert Einhorn, former Assistant Secretary at the U.S. State Department, points out that the U.S. provision of security equipment may require an export license. This type of assistance would also represent a change in US policy, which has been unwilling to supply any “dual-use” equipment to facilities in non-nuclear weapon states that are not subject to the safeguards systems of the International Atomic Energy Agency (IAEA). Virtually all of the facilities in Pakistan’s nuclear weapons complex fall into this category.

Cooperation: First Thoughts

The provision of any assistance requires the United States to carry on a sustained dialogue with Pakistan. Whether this dialogue is occurring is unclear.

Secretary of State Colin Powell told reporters on his mid-October flight to Pakistan that he expected to talk with President Musharraf about nuclear weapons safety. 10 The Washington Times reported after Powell’s visit that Pakistan had rejected a U.S. proposal to provide security for its nuclear arsenal.11 The stated reason was Pakistani fears that U.S. personnel could block Pakistan’s deployment of its nuclear weapons.

Prior to Powell’s trip to South Asia, the New York Times reported that U.S. and Pakistani officials had discussed assistance.12 However, the State Department subsequently denied this media report.

Longer term assistance

Assuming that the United States and Pakistan will cooperate on the provision of assistance, a formula for providing the assistance discussed above is straightforward and certain types of assistance can be provided quickly. Meetings, briefings, and conferences could be held either inside or outside Pakistan. The sponsors could include the U.S. government, other interested governments, or nongovernmental organizations. The IAEA may be able to participate constructively in the discussion over generic physical protection guidelines and practices.

The United States and Pakistan could draw up a list of security equipment that the United States would provide.  The United States would need to invest in the effort of obtaining the necessary export licenses.</p><p>

Non-governmental groups or experts can play a role in providing certain types of assistance.  Case studies based on open information or unclassified information about nuclear weapons security may be appropriate subjects.  These subjects may be difficult for the U.Sgovernment to broach because of internal classification or policy constraints.</p


In the event of an emergency involving Pakistan’s nuclear assets, the United States should be prepared to act quickly if President Musharraf asks for assistance. Toward that end, the United States should decide now what type of assistance it is willing to provide and under what circumstances.

The United States should evaluate various scenarios that may lead Pakistan to ask for assistance. Scenarios include attempts to steal fissile material or nuclear weapons, the successful theft of sensitive items, or the realization of dramatic weaknesses in material accounting, control and protection systems at particular facilities. Certain types of insider threats may also lead Pakistan to ask for assistance. The U.S. government should prepare contingency plans for assisting Pakistan under these various worst-case scenarios.

If the U.S. government anticipates providing Pakistan with dual-use equipment under these scenarios, it should take steps now to ensure that the process of obtaining export licenses does not slow down the assistance unnecessarily. In case Pakistan would ask for assistance in recovering nuclear assets, the United States should decide the type of assistance it can provide in this area. It should also plan and practice how to provide such assistance.

A Final Note: What about a Military Coup?

Several observers have suggested that if Pakistan suffers a coup by forces hostile to the United States, the US military should be ready to provide security over the nuclear weapons (or even to take the weapons out of Pakistan entirely) without the permission of the Pakistani authorities. 13 Others have raised the possibility of asking President Musharraf to allow the United States or China to take possession of Pakistan’s nuclear weapons during a coup.

Although such responses appear possible in theory, their implementation could be extremely difficult and dangerous. A U.S. military action to seize or cripple Pakistan’s strategic nuclear assets may encourage India to take similar action, in essence to finish the job. Even if India does nothing, a new Pakistani government may launch any remaining nuclear weapons at U.S. forces or against India.

In addition, removing the nuclear weapons would not be enough. The new government would inherit the facilities to make nuclear weapons. Extensive bombing would thus be required at several nuclear sites, including the relatively large Khushab reactor and New Labs reprocessing plant. These types of attacks risk the release of a large amount of radiation if they are to ensure that the facility is not relatively quickly restored to operation. For example, bombing the facility so as to bring the roof down on the reactor core or hot cells is unlikely to be sufficient.

Such harsh contingencies may be important to consider in order to protect the vital interests of the United States and its allies. A better strategy, however, is to take appropriate steps to minimize the likelihood that such catastrophic scenarios materialize.


1. A shorter, less comprehensive discussion of principles to provide assistance to Pakistan to secure its nuclear weapons and fissile materials is presented in David Albright, Kevin O’Neill and Corey Hinderstein, Securing Pakistan’s Nuclear Arsenal: Principles for Assistance,” ISIS Issue Brief, October 4, 2001. 1 [Back to the text]

2. “Pakistani Nuclear Assets are Safe: Spokesman Says,” Kyodo News Service, October 2, 2001. 2[Back to the text]

3. Interview on Larry King Live, CNN, October 22, 2001. Transcript available here. 3[Back to the text]

4. “Pakistan’s Nuclear Dilemma,” Carnegie Endowment for International Peace, Non-Proliferation Project Roundtable, October 2, 2001. Transcript available here. 4 [Back to the text]

5. ISIS assessments of the Pakistani nuclear weapons program can be found here. 5 [Back to the text].

6. David Albright, “India’s and Pakistan’s Fissile Material and Nuclear Weapons Inventories, End of 1999,” October 11, 2000. 6 [Back to the text]

7. A set of partially assembled components is considered a nuclear weapon here. 7[Back to the text]

8. One-point safe describes the degree of safety in a nuclear weapon. In the United States, it is a characteristic of a nuclear weapon which, upon undergoing one-point detonation initiated anywhere in the high explosive system, has a probability of no greater than one in a million of producing a nuclear yield in excess of four pounds of TNT equivalent. 8 [Back to the text]

9. For more information about South Africa’s nuclear weapons storage practices, see David Albright and Corey Hinderstein, “South Africa’s Nuclear Weapons Storage Vault,” ISIS Issue Brief, October 4, 2001. 9 [Back to the text]

10. Secretary Powell, Press Briefing on Board Plane En Route to Pakistan, October 16, 2001. Transcript available here. 10 [Back to the text]

11. “Pakistan Rejects Help,” The Washington Times, October 19, 2001. 11 [Back to the text]

12. Douglas Frantz, “U.S. and Pakistan Discuss Nuclear Security,” The New York Times, October 1, 2001. 12 [Back to the text]

13. See for example, Bruce Blair, “The Ultimate Hatred is Nuclear,” The New York Times, October 21, 2001. 13 [Back to the text]

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