Pakistan Nuclear Weapons

A Brief History of Pakistan's Nuclear Program

Pakistan's nuclear weapons program was established in 1972 by Zulfiqar Ali Bhutto, who founded the program while he was Minister for Fuel, Power and Natural Resources, and later became President and Prime Minister. Shortly after the loss of East Pakistan in the 1971 war with India, Bhutto initiated the program with a meeting of physicists and engineers at Multan in January 1972.

India's 1974 testing of a nuclear "device" gave Pakistan's nuclear program new momentum. Through the late 1970s, Pakistan's program acquired sensitive uranium enrichment technology and expertise. The 1975 arrival of Dr. Abdul Qadeer Khan considerably advanced these efforts. Dr. Khan is a German-trained metallurgist who brought with him knowledge of gas centrifuge technologies that he had acquired through his position at the classified URENCO uranium enrichment plant in the Netherlands. Dr. Khan also reportedly brought with him stolen uranium enrichment technologies from Europe. He was put in charge of building, equipping and operating Pakistan's Kahuta facility, which was established in 1976. Under Khan's direction, Pakistan employed an extensive clandestine network in order to obtain the necessary materials and technology for its developing uranium enrichment capabilities.

In 1985, Pakistan crossed the threshold of weapons-grade uranium production, and by 1986 it is thought to have produced enough fissile material for a nuclear weapon. Pakistan continued advancing its uranium enrichment program, and according to Pakistani sources, the nation acquired the ability to carry out a nuclear explosion in 1987.

Nuclear Tests

On May 28, 1998 Pakistan announced that it had successfully conducted five nuclear tests. The Pakistani Atomic Energy Commission reported that the five nuclear tests conducted on May 28 generated a seismic signal of 5.0 on the Richter scale, with a total yield of up to 40 KT (equivalent TNT). Dr. A.Q. Khan claimed that one device was a boosted fission device and that the other four were sub-kiloton nuclear devices.

On May 30, 1998 Pakistan tested one more nuclear warhead with a reported yield of 12 kilotons. The tests were conducted at Balochistan, bringing the total number of claimed tests to six. It has also been claimed by Pakistani sources that at least one additional device, initially planned for detonation on 30 May 1998, remained emplaced underground ready for detonation.

Pakistani claims concerning the number and yields of their underground tests cannot be independently confirmed by seismic means, and several sources, such as the Southern Arizona Seismic Observatory have reported lower yields than those claimed by Pakistan. Indian sources have also suggested that as few as two weapons were actually detonated, each with yields considerably lower than claimed by Pakistan. However, seismic data showed at least two and possibly a third, much smaller, test in the initial round of tests at the Ras Koh range. The single test on 30 May provided a clear seismic signal.

DEVICE DATE YIELD

[announced] YIELD

[estimated] [boosted device?] 28 May 1998 25-36 kiloton total 9-12 kiloton Fission device 28 May 1998 12 kiloton Low-yield device 28 May 1998 sub-kiloton -- Low-yield device 28 May 1998 sub-kiloton -- Low-yield device 28 May 1998 sub-kiloton -- Fission device 30 May 1998 12 kiloton 4-6 kiloton Fission device not detonated 12 kiloton -- This table lists the nuclear tests that Pakistan claims to have carried out in May 1998 as well as the announced yields. Other sources have reported lower yields than those claimed by Pakistan. The Southern Arizona Seismic Observatory reports that the total seismic yield for the May 28th tests was 9-12 kilotons and that the yield for the May 30th tests was 4-6 kilotons.

According to a preliminary analysis conducted at Los Alamos National Laboratory, material released into the atmosphere during an underground nuclear test by Pakistan in May 1998 contained low levels of weapons-grade plutonium. The significance of the Los Alamos finding was that Pakistan had either imported or produced plutonium undetected by the US intelligence community. But Lawrence Livermore National Laboratory and other agencies later contested the accuracy of this finding.

These tests came slightly more than two weeks after India carried out five nuclear tests of its own on May 11 and 13 and after many warnings by Pakistani officials that they would respond to India.

Pakistan's nuclear tests were followed by the February 1999 Lahore Agreements between Prime Ministers Vajpayee and Sharif. The agreements included confidence building measures such as advance notice of ballistic missile testing and a continuation of their unilateral moratoria on nuclear testing. But diplomatic advances made that year were undermined by Pakistan's incursion into Kargil. Under US diplomatic pressure, Prime Minister Sharif withdrew his troops, but lost power in October 1999 due to a military coup in which Gen. Pervez Musharraf took over.