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.
Pakistan Nuclear Weapons - A Chronology
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.
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