India's nuclear program faced significant challenges following the country's first nuclear test, codenamed Smiling Buddha, in 1974. The Nuclear Suppliers Group (NSG), formed in response to the test, imposed a technological embargo on India (and Pakistan, which was pursuing its own nuclear program). This embargo severely hampered India's nuclear development due to a lack of indigenous resources and a dependence on imported technology and assistance.
Prime Minister Indira Gandhi, in an effort to ease international tensions, declared to the International Atomic Energy Agency (IAEA) that India's nuclear program was intended for peaceful purposes, despite authorizing preliminary work on a hydrogen bomb. However, the state of emergency in 1975 and the subsequent political instability left the nuclear program without clear leadership and direction. Despite these setbacks, work on the hydrogen bomb continued, albeit slowly, under mechanical engineer M. Srinivasan.
Prime Minister Morarji Desai, who was known for his advocacy of peace, initially paid little attention to the nuclear program. However, in 1978, Desai's government transferred physicist Raja Ramanna to the Indian Ministry of Defence and re-accelerated the nuclear program.
The discovery of Pakistan's clandestine atomic bomb program, which was more militaristically structured compared to India's, added urgency to India's nuclear efforts. It was evident that Pakistan was close to succeeding in its nuclear ambitions.
In 1980, Indira Gandhi returned to power, and under her leadership, the nuclear program regained momentum. Despite ongoing tensions with Pakistan, particularly over the issue of Kashmir, and international scrutiny, India continued to advance its nuclear capabilities. The program made significant strides under the leadership of Dr. A.P.J. Abdul Kalam, an aerospace engineer, particularly in the development of hydrogen bombs and missile technology.
The political landscape shifted again in 1989 with the Janata Dal party, led by V.P. Singh, coming to power. Diplomatic tensions with Pakistan intensified, especially over the Kashmir insurgency, and the Indian missile program achieved success with the development of the Prithvi missiles.
Successive Indian governments were cautious about conducting further nuclear tests due to fear of international backlash. However, the public support for the nuclear program was strong, leading Prime Minister Narasimha Rao to consider additional tests in 1995. These plans were halted when American intelligence detected test preparations at the Pokhran Test Range in Rajasthan. U.S. President Bill Clinton exerted pressure on Rao to stop the tests, and Prime Minister Benazir Bhutto of Pakistan vocally criticized India's actions.
In 1998, under Prime Minister Atal Bihari Vajpayee, India conducted a series of nuclear tests, Pokhran-II, becoming the sixth country to join the nuclear club. These tests were conducted with utmost secrecy to avoid detection, involving meticulous planning by scientists, military officers, and politicians. The successful completion of these tests marked a significant milestone in India's nuclear journey, asserting its position as a nuclear power despite international criticism and regional tensions.