In 2009, India launched the INS Arihant (S-2) – the lead vessel in a class of three or four SSBNs. The second submarine of this class, INS Arighat (S-3), followed in 2017, and is yet to be officially commissioned into service. The Arihant-class not only completes the nuclear triad of the country, but also provides survivable platforms for a possible second strike. Displacing around 6,000 tonnes, they are relatively small SSBNs, but still carry powerful armament, including either 12 K-15 or four K-4 ballistic missiles with a maximum range of around 3,500km. A follow-up class of slightly bigger SSBNs is expected to carry between eight and 12 K-4s, while the development of longer-ranged weapons – like the S-5 and K-6 – is reportedly underway. (Artwork by Ivan Zajac)