Look at Indiaâ€™s underwater Punch With Trigger Happy Nuclear Neighbour by you side and Indiaâ€™s â€œno-first-useâ€ nuclear policy which prohibited the pre-emptive use of nuclear weapons. Question was not "why" but "when" India will develop a submarine launched missile for to complete underwater leg of the nuclear triad, which always has been regarded as the most survivable. SLBM (submarine-launched ballistic missile) and SLCM (submarine-launched cruise missile) will be the backbone of Indiaâ€™s underwater nuclear deterrence. Indiaâ€™s SLBM (submarine-launched ballistic missile) K-15 Sagarika: on 27 January 2013 which was twelfth and final development trial of the K-15 missile, India officially Gate crashed into Exclusive club of countries with capabilities to develop and launch missiles from a submarine , missile tests were conducted from a submerged pontoon 50 metres (160 ft) beneath the surface off the coast of Visakhapatnam. Missile will be first of Indiaâ€™s SLBMâ€™s to be deployed in Indiaâ€™s Nuclear Submarine INS Arihant. With range of 700km to 1000km, missile is specifically developed to counter attack Pakistan in event of nuclear war. K-4: Considered Indiaâ€™s Black Project, officially not much has been talked about it but, on contrary to the popular belief, missile will not be based on any current ICBM of India but will be different, It has been speculated that missile will have two variants one with lesser payload but with higher range (4500km) and other with Higher payload and reduced range (3500km). DRDO has hinted possibility of a Land based version based on K-4 missile, Sources have informed idrw.org in past that missile will be ready to be integrated in INS Arihant in next few years. K-5: Details of the Missile which is also known has K-X is another highly secretive missile under development ,but Status of this missile is still unclear and it is likely that it will be ready only for deployment in future variants of Arihant class submarines of the Indian Navy. Speculative range of the missile reported in media is 6000km to 8000km. Indiaâ€™s SLCM (submarine-launched cruise missile) BrahMos-1 SLCM: India on 20 March 2013 successfully test fired anti-ship variant of Brahmos for the first time from a submerged pontoon near Visakhapattanam at the coast of Bay of Bengal , once Indiaâ€™s Nuclear submarine INS Arihant completes its sea trails and enters Weapons testing phase submarine variant of BrahMos -1 will be tested from INS Arihant . Nirbhay SLCM: Submarine launched variant of Nirbhay will be ready around 2015 and first launch might take place from submerged pontoon and later will see integration with Arihant class submarines.