Nuclear

In the mid-1970s, Pakistan took the uranium enrichment route to acquiring a nuclear weapons capability. By the mid-1980s, Pakistan had a clandestine uranium enrichment facility, and as early as 1989 to1990, the United States concluded that Islamabad had acquired the capability to assemble a first-generation nuclear device. According to 2010 estimates by the International Panel on Fissile Materials (IPFM), Pakistan has accumulated a stockpile of 2.6 ± 1 tons of highly enriched uranium (HEU). [1] In 1998, Pakistan commissioned the Khushab I research reactor, which is capable of yielding 10 to 15kg of weapons-grade plutonium annually. Since then Khushab II has also become functional. According to the United States, China helped Pakistan by providing nuclear-related materials, scientific expertise, and technical assistance. United States intelligence estimates in 2011 put the number of deployed weapons in the mid-90s at 110. [2] In addition, according to the IFPM's 2010 report, Islamabad has manufactured sufficient fissile material to assemble 40 to 100 more weapons. [3]

Islamabad conducted nuclear tests in May 1998, shortly after India conducted its own nuclear tests, and declared itself a nuclear weapon state. Pakistan is not a signatory to the Treaty on the Non-Proliferation of Nuclear Weapons (NPT). It is also not a party to the Comprehensive Nuclear Test Ban Treaty (CTBT) and has linked its position on the treaty to that of New Delhi's policy on the CTBT.[4] In recent years, Islamabad has sought to strengthen its command-and-control system, especially since the revelations of the A.Q. Khan network's activities between 2003 and 2004. These measures have also included legislation and organizational initiatives dealing with export control and nuclear safety matters.

Islamabad has also sought its own version of a civilian nuclear cooperation agreement similar to the U.S.-India nuclear deal, including a similar exemption for itself from Nuclear Suppliers Group (NSG) regulations. So far there is no indication that the United States and other members of the NSG would consider such initiatives.

The security of Pakistan's nuclear weapons from proliferation networks and terrorist and insurgent groups in the country has been a key concern in recent years. Even though officially the A.Q. Khan proliferation network has been disbanded, suspicions continue in the international community over whether Islamabad has disclosed all relevant information on the network. In addition, the rapid expansion of Taliban control of areas in western Pakistan, as well as increased terrorist and insurgent attacks in the country, have further called into question the security of Islamabad's nuclear facilities and warheads.

Pakistan's oft-repeated official stance is that the Khan network is a "closed chapter" and that all investigations are complete. Moreover it has repeatedly asserted that its nuclear program is under strict control and that it is inconceivable that Taliban insurgents could access or attack its nuclear facilities and nuclear materials. In order to strengthen the security of Islamabad's nuclear weapons program, the United States has provided various levels of assistance to Pakistan.[5]

Biological

While Pakistan is not known to possess biological weapons, it has talented biomedical and biochemical scientists and well-equipped laboratories, which would allow it to quickly establish a sophisticated biological warfare (BW) program should the government so desire. Indeed, the United States reported in 1996 that Islamabad had been "conducting research and development with potential BW applications." It is not known whether this potential has since been realized. Pakistan signed the Biological and Toxin Weapons Convention (BWC) in April 1972 and ratified it in 1974.

Chemical

Pakistan signed the Chemical Weapons Convention (CWC) in 1993 and ratified the treaty in 1997. Islamabad has apparently made no admissions in its treaty-mandated declarations of having possessed chemical weapons. While some analysts have alleged that Pakistan possesses a chemical weapons program, there is no substantiated evidence in publicly available literature that Pakistan has ever possessed chemical weapons.

Missile

Pakistan is developing both solid- and liquid-fueled ballistic missiles, based extensively on foreign systems. In the early 1990s, Pakistan purchased a small number of 300km-range M-11 ballistic missiles from China; Beijing also built a turnkey ballistic missile manufacturing facility at Tarwanah, a suburb of Rawalpindi. By the late 1990s, China helped Pakistan develop the 750km-range, solid-fueled Shaheen-1 ballistic missile, which was last tested in October 2002. In the late 1990s, Pakistan also acquired a small number of 1,500km-range Nodong (Ghauri) ballistic missiles from North Korea. As of 2008, nuclear-capable ballistic missiles inducted by Pakistan into its defense services included the Ghaznavi (Hatf-3, range 400 km), Shaheen-I (Hatf-4, range 450 km), and the Ghauri (Hatf-5, range 1,200 km).[3] Missiles under development include the 2,000 to 2,500 km range Shaheen-II, which was first tested in 2004.

In addition to ballistic missiles, cruise missiles are increasingly part of Pakistan's nuclear delivery plans. Its flagship cruise missile is the Babur, which has a range of 500 to 700 km and was first tested in August 2005. In August 2007, Pakistan tested a second nuclear-capable cruise missile, the air-launched Ra'ad (Hatf-8).

Sources:

[1] "Global Fissile Material Report 2010," International Panel on Fissile Materials, Fifth Annual Report, December 2010,www.fissilematerials.org.
[2] David E. Sanger and Eric Schmitt, "Pakistani Nuclear Arms Pose Challenges to U.S. Policy," The New York Times, 31 January 2011, www.nytimes.com.
[3] "Global Fissile Material Report 2010," International Panel on Fissile Materials, Fifth Annual Report, December 2010, www.fissilematerials.org; and David E. Sanger and Eric Schmitt, "Pakistani Nuclear Arms Pose Challenges to U.S. Policy," The New York Times, 31 January 2011, www.nytimes.com.
[4] "Arms Control and Proliferation Profile: Pakistan," Fact Sheet, Arms Control Association, November 2007, www.armscontrol.org.
[5] Sharad Joshi and Togzhan Kassenova, "Cooperative Threat Reduction and Pakistan," Issue Brief, Nuclear Threat Initiative, 4 August 2008, www.nti.org.