After the Independence of India, we faced many wars with our neighbours (China and Pakistan) and they attacked us because they thought that we were not strong. To prove our strength we needed powerful weapons that can destroy our enemies.
Peace cannot be obtained by mutual benefits or talks, it can only be achieved by strength so to be the peaceful nation we need to become one of the most powerful nations of the world.
To obtain the strength we made our nuclear warheads. They were built to show the strength of our country.
We needed proper technology to build a nuclear warhead but no nation was supporting us at that time to obtain such technology. So to obtain technology and strength for its safety India conducted the Pokhran test.
What is the Pokhran Test ?
The Pokhran-II tests were a series of five nuclear bomb test explosions conducted by India at the Indian Army’s Pokhran Test Range in May 1998. It was the second instance of nuclear testing conducted by India; the first test, code-named Smiling Buddha, was conducted in May 1974.
The tests achieved their main objective of giving India the capability to build fission and thermonuclear weapons with yields up to 200 kilotons.The then-Chairman of the Indian Atomic Energy Commission described each one of the explosions of Pokhran-II to be “equivalent to several tests carried out by other nuclear weapon states over decades”. Subsequently, India established computer simulation capability to predict the yields of nuclear explosives whose designs are related to the designs of explosives used in this test.

Pokhran-II consisted of five detonations, the first of which was a fusion bomb while the remaining four were fission bombs.The tests were initiated on 11 May 1998, under the assigned code name Operation Shakti, with the detonation of one fusion and two fission bombs. On 13 May 1998, two additional fission devices were detonated, and the Indian government led by Prime Minister Atal Bihari Vajpayee shortly convened a press conference to declare India as a full-fledged nuclear state. The tests resulted in a variety of sanctions against India by a number of major countries including Japan and the United States.
Many names have been assigned to these tests; originally these were collectively called Operation Shakti–98, and the five nuclear bombs were designated Shakti-I through to Shakti-V. More recently, the operation as a whole has come to be known as Pokhran II, and the 1974 explosion as Pokhran-I.
Reactions from other nations
Strong criticism was drawn from Canada on India’s actions and its High Commissioner. Sanctions were also imposed by Japan on India and consisted of freezing all new loans and grants except for humanitarian aid to India.
Some other nations also imposed sanctions on India, primarily in the form of suspension of foreign aid to India and government-to-government credit lines. However, the United Kingdom, France, and Russia refrained from condemning India.
Reference from :- https://en.wikipedia.org/wiki/Pokhran-II