What K-4 Nuclear Capable Ballistic Missile Means For India's Submarine Force

New Delhi: India's strategic capabilities made a major advancement with the first successful test of its K-4 submarine-launched ballistic missile (SLBM) from an operational SSBN on November 27.
The nuclear-capable missile, with a range of 3,500 km, was launched from INS Arighat, India’s second operational nuclear-powered ballistic missile submarine (SSBN), which was commissioned earlier this year.

Prior to this, India had conducted at least two tests of the missile, launching it from an underwater pontoon.

How K-4 Nuclear Missile Adds Teeth To Naval Deterrence

This advancement marks a significant enhancement to India’s nuclear triad, offering a strong second-strike capability that strengthens deterrence and mitigates operational limitations. A nuclear triad encompasses the ability to deliver nuclear weapons via three platforms: land-based intercontinental ballistic missiles (ICBMs), air-launched bombs or cruise missiles, and submarine-launched ballistic missiles (SLBMs).

Can Hit Targets In Pakistan And China

The successful K-4 test significantly shifts this dynamic. With a range of 3,500 km, an SSBN equipped with K-4 missiles can strike high-value targets across much of China, including Beijing, as well as any location in Pakistan, all while operating securely from protected bastions in the northern Bay of Bengal. This operational advantage minimizes vulnerability to anti-submarine warfare (ASW) measures and boosts survivability, which is crucial for maintaining credible deterrence under India’s no-first-use policy.