Nuclear warfare
After World War II, nuclear weapons were also developed by the Soviet Union (1949), the United Kingdom (1952), France (1960), and the People's Republic of China (1964), which contributed to the state of conflict and extreme tension that became known as the Cold War. In 1974, India, and in 1998, Pakistan, two countries that were openly hostile toward each other, developed nuclear weapons. Israel (1960s) and North Korea (2006) are also thought to have developed stocks of nuclear weapons, though it is not known how many. The Israeli government has never admitted or denied to having nuclear weapons, although it is known to have constructed the reactor and reprocessing plant necessary for building nuclear weapons. South Africa also manufactured several complete nuclear weapons in the 1980s, but subsequently became the first country to voluntarily destroy their domestically made weapons stocks and abandon further production (1990s). Nuclear weapons have been detonated on over 2,000 occasions for testing purposes and demonstrations.
Pakistan and weapons of mass destruction
Pakistan is one of nine states to possess nuclear weapons. Pakistan began development of nuclear weapons in January 1972 under Prime Minister Zulfikar Ali Bhutto, who delegated the program to the Chairman of the Pakistan Atomic Energy Commission (PAEC) Munir Ahmad Khan with a commitment to having the bomb ready by the end of 1976. Since PAEC, consisting of over twenty laboratories and projects under nuclear engineer Munir Ahmad Khan, was falling behind schedule and having considerable difficulty producing fissile material, Abdul Qadeer Khan was brought from Europe by Bhutto at the end of 1974. As pointed out by Houston Wood, Professor of Mechanical & Aerospace Engineering, University of Virginia, Charlottesville, in his article on gas centrifuges, "The most difficult step in building a nuclear weapon is the production of fissile material"; as such, this work in producing fissile material as head of the Kahuta Project was pivotal to Pakistan developing the capability to detonate a nuclear bomb by the end of 1984.