India has fulfilled its ‘Nuclear Triad’ potential through a quiet and sustained effort, providing a long-term and reliable foundation for its national security. Its most secret and invincible link is SSBN i.e. nuclear submarines. With these Arihant class submarines, India has joined the elite global group that has nuclear powered and nuclear armed submarines. Of these, INS Arihant and INS Arighat are already in service, INS Aridhaman will soon join the Navy and the fourth submarine is currently being built.
These submarines are capable of making the enemy an accurate target by hiding in the immense depths of the sea. These four submarines have so much power that they can “destroy any major landmass or continent”. This capability comes from advanced missiles like the K-4 deployed in them, which can deliver heavy nuclear warheads up to 3,500 km away. In future, this power will increase manifold with the arrival of K-5 missiles with a range of 5,000-6,000 km.
The four nuclear submarines of the Arihant-class are extremely lethal in terms of numbers. An Arihant-class SSBN can typically carry 12 K-15 missiles or 4 to 8 K-4 ballistic missiles. 1 to 2 nuclear warheads can be installed on each K-4 missile. This means that a single submarine has the capability to fire 8 to 16 nuclear bombs from the depths of the sea. Combining all four submarines, this number reaches more than 30 to 60 nuclear warheads—enough to destroy many major cities, industrial areas, or continental bases at once. This is the reason why these four nuclear submarines of India alone have the capability to cause huge damage to any continent.
Nuclear Deterrence does not mean fighting war, but preventing war from happening. According to India’s ‘No First Use (NFU) policy, India will not launch a nuclear attack first, but if attacked, it will definitely respond. This is the reason why India’s security depends on the strong capability of second strike. Ground-based missile bases can be destroyed, airports can be attacked, and the country’s leadership can also be targeted.
But it is very difficult to find and destroy a nuclear missile submarine hidden in the depths of the sea. For this reason, the world’s major nuclear powers keep their most reliable nuclear weapons in the sea. America rests its strength on Ohio-class submarines, Britain’s entire nuclear deterrence is based on only four Vanguard-class submarines, China is also rapidly increasing the number of its Jin-class submarines. India has adopted a clear strategy despite limited resources, fewer submarines, but a completely reliable and effective force.
India’s maritime nuclear deterrence rests on Arihant-class SSBN submarines, built under the Advanced Technology Vehicle (ATV) programme. The real job of these submarines is to remain hidden and respond when needed. Every Arihant-class submarine is powered by a nuclear reactor, allowing it to remain at sea for very long periods. The ballistic missiles (SLBM) mounted on them are the safest part of India’s nuclear infrastructure.
According to the estimates of the Arms Control Center in May 2025, India has about 170–180 nuclear weapons. Among these, the weapons deployed at sea are less in number, but they are the most effective and reliable in preventing war.
India’s nuclear strategy is completely different from China’s rapid nuclear expansion and Pakistan’s reliance on tactical nuclear weapons. India neither has battlefield nuclear weapons, nor a policy to respond immediately upon receiving warning of an attack, nor a system that is ready at all times and takes quick decisions. Instead, India has built a nuclear force that may not strike immediately but has the capability to deliver a devastating response if needed.
This is the real psychological effect of Nuclear Deterrence. The enemy will always fear that the submarine may be hidden anywhere—it is present, armed and will definitely respond if attacked. Four SSBN submarines ensure this confidence and security.
With the induction of INS Aridhaman into the Navy, it will become clear that India’s Maritime Nuclear Deterrence has now become completely permanent, strong and mature. This is happening at a time when Pakistan is more dependent on nuclear weapon threats, China is rapidly increasing its naval presence in the Indian Ocean and the global nuclear balance is under pressure. In this situation, India has adopted a policy of giving a confident and thoughtful response instead of provocation.
India’s Maritime Nuclear Deterrence is adequate and reliable. With just four SSBN submarines, India has secured its second strike capability, strengthened the no-first-use principle, avoided a volatile arms race, and established itself among the world’s most elite nuclear strategic powers. The real power lies not in the missiles, but in the certainty that if attacked, there will be a response.
