Context: A successful trial of the nuclear capable Shaurya missile was conducted by India recently. Shaurya is a land-based parallel of the submarine launched K-15 missile. 

• These ballistic weapons belong to the K missile family — codenamed after late Dr APJ Abdul Kalam — which are launched from Arihant class of nuclear submarines.

About K-Missile Family 

• The K family of missiles are primarily Submarine Launched Ballistic Missiles (SLBMs), which have been indigenously developed by Defence Research and Development Organisation (DRDO) and are named after Dr Kalam, the centre figure in India’s missile and space programmes who also served as the 11th President of India.
• The development of these naval platform launched missiles began in the late 1990s as a step towards completing India’s nuclear triad — the capability of launching nuclear weapons from land, sea and air based assets.
• Because these missiles are to be launched from submarines, they are lighter, smaller and stealthier than their land-based counterparts, the Agni series of missiles which are medium and intercontinental range nuclear capable ballistic missiles.
• While K family are primarily submarine-fired missiles to be fired from India’s Arihant class nuclear powered platforms, the land and air variants of some of its members have also been developed by the DRDO.
• Shaurya, whose user trial was conducted recently, is a land variant of short range SLBM K-15 Sagarika, which has a range of at least 750 kilometers.
• India has also developed and successfully tested multiple times the K-4 missiles from the family which has a range of 3500 km. 
• It is reported that more members of K-family — reportedly to have been codenamed K-5 and K-6 — with ranges of 5000 and 6000 km are also under development. 
• The early development trials of K-15 and K-4 missiles had begun in the early 2010s.

Strategic importance of SLBMs 

• The capability of being able to launch nuclear weapons submarine platforms has great strategic importance in context of achieving a nuclear triad, especially in the light of ‘no first use’ policy of India.
• The sea-based underwater nuclear capable assets significantly increases the second strike capability of a country and thus boosts its nuclear deterrence.
• These submarines can not only survive a first strike by the adversary but also can launch a strike in retaliation thus achieving Credible Nuclear Deterrence.
• The 2016 commissioned nuclear powered Arihant submarine and its class members which in the pipeline, are the assets capable of launching missiles with nuclear warheads.
• Shaurya, like many of the modern missiles, is a canister-based system, which means that it is stored and operated from specially designed compartments. 
• In the canister, the inside environment is controlled thus along with making its transport and storage easier, the shelf life of weapons also improves significantly.
• While DRDO has been conducting these tests, there has not been any official communication from the agency about them, possibly because of classified nature of K family missile projects and their close link to the Advanced Technology Vehicle (ATV) project of which Arihant class vessels are part of. 
• These recent tests of these systems can also be looked at as a strong message to China and Pakistan in light of the present situation in the region.