Goa was liberated on 19th December, 1961 and the small state joined the mainstream India. In 1962, China attacked India when Pandit Jawaharlal Nehru was the Prime Minister and V.K. Krishna Menon was the Defence Minister of India. Our leaders never expected China to attack India and we were totally unprepared for this. It is during that time this slogan was raised.
The slogan is no longer valid and China cannot be trusted any more. They have annexed Tibet and also some area of India. We should beware of China.
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They coined it after Bandung Conference and propogation of Panchsheel by Jawahar Lal Nehru,who in my opinion was more interested to get Nobvel Peace Prize than the country.In 1955-56 ChouEnLai,chinease PM came and we school students were lined up with Our and Chinease flags and shouting this slogan.We got it in 1962 although they were intruding right since 1954 in AksaiCheen(building a road) ,presented us with beheaded bodies of 5 policemen and what not .List is endless.