Early nuclear programme (1944–1965) Efforts towards building a
nuclear bomb, infrastructure, and research on related
technologies have been undertaken by India since the end of
Second World War. The origins of
India's nuclear programme go back to 1945 when nuclear physicist
Homi Bhabha established the
Tata Institute of Fundamental Research (TIFR) with the aid of
Tata Group. After
Indian independence, the Atomic Energy Act was passed on 15 April 1948, that established the
Indian Atomic Energy Commission (IAEC). In 1954, thee
Department of Atomic Energy (DAE) was established which was responsible for the atomic development programme and was allocated a significant amount of the defence budget in the subsequent years. In 1956, the first
nuclear reactor became operational at
Bhabha Atomic Research Centre (BARC), becoming the first operating reactor in Asia. In 1961, India commissioned a reprocessing plant to produce
weapon grade plutonium. In 1962, India was engaged in a
war with China, and with China conducting its own
nuclear test in 1964, India accelerated its development of nuclear weapons. The incoming prime minister
Lal Bahadur Shastri appointed physicist
Vikram Sarabhai as the head of the nuclear programme and the direction of the programme changed towards using nuclear energy for peaceful purposes rather than military development.
Development of nuclear bomb and first test (1966–1972) as photographed by a US satellite on 19 February 1966 After Shastri's death in 1966,
Indira Gandhi became the prime minister and work on the nuclear programme resumed. The design work on the bomb proceeded under physicist
Raja Ramanna, who continued the nuclear weapons technology research after Bhabha's death in 1966. After India gained military and political initiative over Pakistan in the war, the work on building a nuclear device continued. The hardware began to be built in early 1972 and the Prime Minister authorised the development of a nuclear test device in September 1972. On 18 May 1974, India tested a
implosion-type fission device at the
Indian Army's
Pokhran Test Range under the code name
Smiling Buddha. The test was described as a
peaceful nuclear explosion (PNE) and the
yield was estimated to be between 6 and 10
kilotons.
Aftermath of nuclear tests (1973–1988) While India continued to state that the test was for peaceful purposes, it encountered opposition from many countries. The
Nuclear Suppliers Group (NSG) was formed in reaction to the Indian tests to check international
nuclear proliferation. The
technological embargo and sanctions affected the development of India's nuclear programme. It was crippled by the lack of indigenous resources and dependence on imported technology on certain areas. Though India declared to the
International Atomic Energy Agency (IAEA) that India's nuclear program was intended only for peaceful purposes, preliminary work on a
fusion bomb was initiated. In the aftermath of the
state emergency in 1975 that resulted in the collapse of the
Second Indira Gandhi ministry, the programme continued under
M.R. Srinivasan, but made slow progress. Though the nuclear programme did not receive much attention from incoming Prime Minister
Morarji Desai at first, it gained impetus when Ramanna was appointed to the
Ministry of Defence. With the discovery of
Pakistan's clandestine atomic bomb program, India realised that it was very likely to succeed in its project in a few years. With the return of Indira Gandhi in
1980, the nuclear programme gained momentum. Two new underground shafts were constructed at the Pokhran test range by 1982 and Gandhi approved further nuclear tests in 1982. But the decision was reversed owing to pressure from the United States as it might end up in
nuclear brinksmanship with Pakistan and potential foreign policy implications. Work continued towards weaponizing the nuclear bomb under
V. S. R. Arunachalam and the
Indian missile programme was launched under
A. P. J. Abdul Kalam. The NSG decided in 1992 to require full-scope IAEA safeguards for any new nuclear export deals, which effectively ruled out nuclear exports to India. Though India had stock-piled material and components to be able to construct a dozen nuclear fission bombs, the deliverance mechanism was still under development. With the successful testing of
Agni missile and successful trials involving dropping of similar bombs without fissionable material from
bomber aircraft in 1994, the weaponization became successful. With the
Comprehensive Nuclear-Test-Ban Treaty under discussion and global pressure pushing India to sign, then Indian Prime Minister
Narasimha Rao ordered preparations for further nuclear tests in 1995. Based on the direction of the director of DAE
R. Chidambaram,
S. K. Sikka was tasked with the development of a thermo-nuclear fusion device. In August,
K. Santhanam, the chief technical adviser of DRDO, was appointed the director for carrying out the tests. While water was being pumped out of the shafts constructed more than ten years earlier, American
spy satellites picked up the signs. With Rao's term ending in 1996, the next two years saw multiple governments being formed.
Atal Bihari Vajpayee, who was a strong advocate of nuclear weaponization, came to power following the
1998 general elections. Vajpayee had earlier declared that if re-voted to power, his government would induct nuclear weapons and declare India's might to gather respect. Soon after assuming power in March 1998, Vajpayee organized a discussion with Abdul Kalam and Chidambaram to conduct nuclear tests. On 28 March 1998, he asked to make preparations for a test. == Nuclear test ==