India on Friday added new teeth to its nuclear deterrent by test firing a ballistic missile from INS Arihant, its atomic powered submarine

The Arihant is at the core of India’s nuclear triad, empowering New Delhi to launch atomic weapons from the ground, air and the sea. The Arihant is central to India’s second-strike capability—an ability to potently counterstrike after absorbing a first strike by a hostile force.

India’s land based nuclear deterrent includes land based solid fuelled Agni series of missiles which have a maximum range of around 5,000 kilometres, with a footprint that extends deep into China. Tactical nuclear can be fire by the short range Prithvi missile. India’s recently developed Agni-P has been containerised be fired from mobile launchers.

Today’s launch precedes that 20th Party Congress in China, which is expected to endorse General Secretary Xi Jinping’s controversial leadership tenure by another five years.

In a statement the defence ministry said: “The missile was tested to a predetermined range and impacted the target area in the Bay of Bengal with very high accuracy. All operational and technological parameters of the weapon system have been validated”.

The successful user trial of the SLBM signals the Navy has acquired the training to launch the weapon, which can now become operational.

The ministry said that launch proves the crew’s competence to operate a Strategic Strike Nuclear Submarines (SSBNs).

India has three types of submarines. The SSBN subs are not only powered by a long endurance nuclear engine, they can also fire nuclear tipped ballistic.

India is four Arihant class SSBNs. Sea trials of INS Arighat began in 2017. The final two boats, INS Aridhaman and an unnamed vessel are likely to be much larger than the Arihant.

India also developing six nuclear-powered SSNs SSNs or submarines that are powered by an atomic engine but deploy only conventional missiles. India’s rapidly evolving submarine project includes six Kalvari class French origin Scorpene submarines which will also be retrofitted with Air Independent Propulsion (AIP), which will allow them to stay beneath the surface for a much longer time. The last two of the boats of this class are likely to be equipped with AIP, and the other four will be subsequently retrofitted with the technology.

AIP technology allows a non-nuclear submarine to operate without access to atmospheric oxygen, greatly enhancing their underwater endurance.

“A robust, survivable and assured retaliatory capability is in keeping with India’s policy to have ‘Credible Minimum Deterrence’ that underpins its ‘No First Use’ commitment,” the ministry added, signalling the Arihant’s second-strike capability once armed with Submarine Launch Ballistic Missiles (SLBMs).

INS Arihant was launched on July 26, 2009, by former Prime Minister Manmohan Singh. Its atomic reactor was activated in August 2013.