India successfully tested a K-4, an intermediate-range ballistic missile, on 23 December last year from the nuclear-powered submarine INS Arighaat in the Bay of Bengal. The development confirmed the full integration of missile, submarine and command and control systems.
With a range of roughly 3,500 kilometres, the K-4 has fundamentally altered India’s deterrence equation. It has marked the shift from developmental testing to deployable deterrence, establishing the Bay of Bengal as an active nuclear deterrence space and not merely a testing area.
Doctrinally, it signals continuity. The post-test briefings were communicated with deliberate restraint, reiterating doctrinal continuity. Media reporting paraphrased defence officials repeatedly describing the launch as a routine exercise and nullifying the activity as a response to immediate threats. The emphasis was on operational readiness and reliability, not on signalling power or drawing attention to adversaries.
Additionally, the framing of the tests was in the context of India’s commitment to No First Use, consistent with its nuclear doctrine. The K-4 test was presented in a way to clarify that India was not rewriting its nuclear posture but rather deepening its reliability.
Strategic shift from west to east
For most of India’s post-Independence history, strategic attention has been focused on the western frontiers. The eastern frontiers, in comparison, have been treated with less urgency. While prevention of illegal migration and securing of land borders has been considered vital to India’s national security, the Bay of Bengal has been mostly viewed through a commercial lens rather than a strategic one.
Though it was in 1971 during the Bangladesh Liberation War that the presence of USS Enterprise in the Bay of Bengal exposed a critical strategic vulnerability for India at a decisive moment of war. The coercive signalling exposed India’s maritime vulnerability and internationalised a regional war. India had to seek reassurance from the Soviet Union, leading to visible Soviet naval counter-movements.
But more importantly, this episode determined the future course of India’s maritime strategy and ensured that policymakers and defence experts started reviewing the importance of the Bay of Bengal. The USS Enterprise could not alter the outcome of the 1971 war, but it revealed how strategic pressure could be applied from the sea even when victory was assured on land.
In the following decades, the Bay of Bengal started to see Chinese naval survey vessels, intelligence-gathering ships and submarines appear with increasing frequency. Recently, a French maritime intelligence firm, Unseenlabs, reported a Chinese research vessel operating in the Bay of Bengal near Indian waters, while attempting to conceal its presence by disabling its Automatic Identification System (AIS). The event raised security concerns in New Delhi about covert undersea surveillance or intelligence activities.
Furthermore, groups of China’s People’s Liberation Army (PLA) Navy ships, including destroyers, frigates, and support vessels, have sailed through the Andaman Sea and operated close to the Bay of Bengal before carrying out activities such as search-and-rescue drills as well as escort training under names like ‘Peace and Friendship 2025’. These activities have not been labelled as exercises in the Bay of Bengal, but their proximity is telling of an increasing interest in being operationally close to India’s eastern maritime space.
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Unstable neighbourhood
The Coco Islands, which sit at a critical maritime junction in the Bay of Bengal, just north of India’s Andaman and Nicobar Islands, has also garnered attention recently. The growing presence of China in conflict-ridden Myanmar has had its repercussions on the region. Reports have suggested that China has upgraded airstrips, jetties and communication infrastructure on the islands. The Kyaukphyu Port development and energy pipelines running across Myanmar to China’s Yunnan Province have also transformed the Bay of Bengal into a gateway and now just a regional backyard.
Simultaneously, Bangladesh’s induction of two Chinese-origin submarines as part of military modernisation under its Forces Goal 2030 programme not only represents Dhaka’s first undersea combat capability, expanding its naval reach to the Bay of Bengal, but the acquisition also reflects the deepening defence ties with China. Beyond equipment, cooperation between Bangladesh and China has expanded to training and infrastructure development. Bangladesh’s dedicated submarine base, BNS Pekua, has been built by China, in addition to the technical support that Beijing has provided to Bangladeshi forces.
With continuing instability across India’s eastern neighbourhood and elections in both Bangladesh and Myanmar unlikely to ease internal political tensions, external powers will likely gain further strategic footholds. The Bay of Bengal will continue to remain a space for growing geostrategic contestation and regional rivalries.
After all, it was recently that the ousted Prime Minister of Bangladesh Sheikh Hasina brought up St Martin’s Island again. The island gained prominence after she alleged that the United States had pressured her to hand over the sovereignty of the island in the Bay of Bengal for the US to establish a military base on the island in return for her to remain in power.
Recently, she once again accused the interim government head Muhammad Yunus of “selling” the nation to the United States. In a lengthy social media note, she wrote, “When America wanted St. Martin’s Island, my father did not agree. He had to give his life. And that was my destiny. Because I never had the thought of selling the country to stay in power”. St Martin’s Island’s strategic value would add to any country’s oversight of the Bay of Bengal.
Finally, India’s Eastern Naval Command’s remit has clearly expanded in response to the activity in the Bay of Bengal. Therefore, India’s decision to base its ballistic missile submarine programme on the eastern seaboard is not accidental. While there is doctrinal continuity and commitment to ‘No First Use’, the doctrinal shift is that India’s nuclear deterrence is no longer primarily land-centric. For India, what began in 1971 as a situation of vulnerability has turned into a lesson of learning that has culminated in quiet confidence.
Rami Niranjan Desai is a scholar of Northeast region of India and the neighbourhood. She is a columnist and author and presently Distinguished Fellow at India Foundation, New Delhi. Views are personal.
(Edited by Saptak Datta)
Being a rising super power India has to continuously increase its military strength. And slowly it must become self-sufficient to manufacture most of the military machinery. At the super power level, it is strength – military, economical, technology, R&D, etc. that matters.