New Delhi: If Swami Vivekananda's message of universal brotherhood been followed by the world, history would not have witnessed "dastardly acts" like 9/11 in the US, said Prime Minister Narendra Modi Thursday.

"Had we followed Swami ji's message, history would never have witnessed such dastardly acts as we saw on 11th September 2001 in USA. Let us remember the words of Swami Vivekananda and dedicate ourselves to furthering the cause of unity, brotherhood and world peace," Modi said in a tweet.