India's Indian Ocean Doctrine: The Maritime Power Play Delhi Hasn't Talked About

Executive Summary

While global attention through 2025 and 2026 has fixed on Ukraine, Gaza, and the Iran war, India has been quietly assembling one of the more consequential regional maritime strategies of the decade. Over the past eighteen months, New Delhi has published a new Indian Maritime Doctrine, followed it with a more explicit Indian Maritime Strategy in 2026, expanded its founding SAGAR framework into the broader MAHASAGAR vision covering the wider Global South, commissioned new naval infrastructure on India's island territories and in partner states, and run an unprecedented tempo of multinational naval deployments and exercises. This activity has occurred against a backdrop of accelerating Chinese research-vessel and infrastructure activity across the Indian Ocean Region, and, most strikingly, a direct US military strike inside waters India considers its strategic backyard, when a US submarine sank the Iranian frigate IRIS Dena roughly forty nautical miles off Sri Lanka in March 2026.

This report treats India's Indian Ocean posture as a coherent, if still evolving, grand-strategic doctrine rather than a series of disconnected naval press releases, and asks what it reveals about India's actual willingness and capacity to act as the Indian Ocean's primary security guarantor, at a moment when both Chinese expansion and unrelated great-power military activity are testing that role directly.

Strategic Background

India's modern Indian Ocean doctrine traces to the 2015 articulation of SAGAR, Security and Growth for All in the Region, under Prime Minister Narendra Modi, which framed India as a net security provider committed to a cooperative, rules-based maritime order rather than exclusive dominance. In March 2025, during a visit to Mauritius, Modi announced the doctrine's evolution into MAHASAGAR, Mutual and Holistic Advancement for Security and Growth Across Regions, explicitly extending India's maritime engagement beyond the Indian Ocean proper into the wider Indo-Pacific and the broader Global South. That doctrinal evolution has since been reinforced institutionally: the Indian Navy published its Indian Maritime Doctrine 2025, followed in 2026 by the Indian Maritime Security Strategy, INMSS-2026, which analysts describe as an effort to convert the SAGAR and MAHASAGAR political slogans into more operationally meaningful strategic guidance, addressing earlier criticism that concepts like "Preferred Security Partner" and "First Responder" lacked clear operational definition.

Historical Context

India's maritime posture has historically been secondary to its land-centric strategic culture, shaped by the continental threats posed by Pakistan and China along the Himalayan frontier. That orientation began shifting meaningfully only in the 2000s and accelerated after 2015, driven substantially by growing Indian anxiety over Chinese infrastructure investment across the Indian Ocean Region, including Gwadar port in Pakistan, Hambantota port in Sri Lanka, and deepening ties with the Maldives, developments Indian strategists have long read through a "string of pearls" lens even when Beijing frames them as purely commercial. China's establishment of its first overseas military base in Djibouti in 2017, and its subsequent naval anti-piracy deployments to the Gulf of Aden dating to 2008, demonstrated a sustained, if still limited, Chinese naval presence in waters India had long treated as its natural sphere of influence, giving India's later doctrinal shift from SAGAR to MAHASAGAR a clear strategic rationale rather than a purely rhetorical one.

Current Situation Assessment

As of mid-2026, India's MAHASAGAR framework has moved from declaration to operational substance across multiple tracks. The Indian Ocean Ship SAGAR initiative, under which the Indian Navy deploys vessels crewed jointly with partner nations for training and EEZ patrol support, expanded from its 2025 inaugural deployment aboard INS Sunayna to a second 2026 edition involving personnel from sixteen partner nations, a meaningful increase in participation that the Navy has publicly framed as evidence of MAHASAGAR's growing traction. Exercise MILAN 2026 and the associated International Fleet Review drew seventy-four participating nations and eighty-five warships, including the indigenously built aircraft carrier INS Vikrant, which the Navy has used deliberately to project its "Builder's Navy" narrative of growing self-reliance in naval platforms. Separately, the Indian Navy has continued western Indian Ocean outreach, including a ten-nation joint patrol and counter-piracy exercise involving Comoros, Djibouti, Kenya, Madagascar, Mauritius, Mozambique, Seychelles, South Africa, and Tanzania alongside India, extending MAHASAGAR's reach explicitly into the African littoral in a way SAGAR's original Indian Ocean-only framing did not.

Against this cooperative-security narrative, India's central strategic anxiety, sustained and arguably accelerating Chinese activity, has not abated. Chinese oceanographic and hydrographic research vessels, widely assessed by Indian and allied analysts as serving dual-use intelligence and seabed-mapping functions relevant to future submarine operations, have continued transiting and, at times, seeking port access in Sri Lanka and the Maldives, with reporting indicating Chinese research-vessel activity across the Indian Ocean and Pacific has scaled substantially over the past five years. The most consequential and least discussed development in the region during this period was not Chinese, however: on March 4, 2026, a US submarine torpedoed and sank the Iranian frigate IRIS Dena approximately forty nautical miles off Sri Lanka, an attack that killed dozens and was publicly described by US Defense Secretary Pete Hegseth in triumphant terms. That strike occurred well within India's traditional maritime sphere of interest and close to Sri Lankan territorial waters, without any evident Indian operational role, a fact that has received strikingly little sustained Indian strategic commentary relative to its significance as a demonstration that great-power military action can now occur inside India's own backyard largely independent of Indian awareness or consent.

Power Center Analysis

Four actors define the current Indian Ocean power balance. India remains the resident power with the largest standing naval presence, the deepest historical and cultural ties across the littoral, and now an increasingly articulated doctrine backing that position, but its capacity to translate doctrine into sustained forward presence remains constrained relative to its stated ambitions. China is the primary external challenger, pursuing a dual-track strategy of ostensibly civilian port and research-vessel infrastructure that Indian and allied analysts consistently assess as laying groundwork for eventual military access, while explicitly avoiding, at least for now, direct challenge to the US Fifth Fleet's regional primacy. The United States remains the dominant extra-regional military power, as the March 2026 IRIS Dena strike demonstrated starkly, operating with a degree of freedom of action in the Indian Ocean that neither China nor India currently possesses, and one that India has not meaningfully contested despite the strike's proximity to Sri Lankan waters. Littoral states, particularly Sri Lanka and the Maldives, function as the contested terrain between Indian and Chinese influence, with both governments navigating between reassurances to New Delhi and continued economic and diplomatic engagement with Beijing, a hedging pattern reinforced by the Maldives' post-2023 "India Out" political shift under President Mohamed Muizzu even as relations have shown signs of gradual stabilization since.

Military and Security Implications

India's naval modernization, symbolized by the indigenous carrier INS Vikrant and the Navy's growing emphasis on domestic shipbuilding capacity, reflects a genuine, if incremental, effort to close the credibility gap between MAHASAGAR's stated ambitions and India's actual blue-water capability. The Indian Maritime Doctrine 2025's recognition of "No War No Peace" conditions and multi-domain operations signals institutional acknowledgment that Indian Ocean security competition increasingly plays out below the threshold of open conflict, through research-vessel intelligence gathering, port-access diplomacy, and grey-zone presence rather than direct naval confrontation, an assessment consistent with the pattern of Chinese activity across Sri Lankan and Maldivian waters over the past several years. The IRIS Dena incident, meanwhile, exposes a different and less comfortable security implication: India's doctrine assumes a central Indian role in managing Indian Ocean security dynamics, yet the region's most significant recent use of lethal force occurred as a byproduct of an entirely separate US-Iran conflict, with India functioning as a bystander rather than a participant or even a consulted party, raising real questions about how much practical control MAHASAGAR's "net security provider" framing actually confers when extra-regional powers choose to act unilaterally.

Economic and Trade Impact

The Indian Ocean carries a substantial share of global seaborne energy and containerized trade, passing through chokepoints including the Strait of Malacca, the Bab-el-Mandeb, and the Strait of Hormuz, giving India's maritime posture direct economic stakes well beyond regional security symbolism. MAHASAGAR's explicit pairing of security cooperation with economic connectivity, sustainable development, and technology partnership reflects an Indian bet that economic statecraft, port development, capacity building, and Blue Economy initiatives, can compete with Chinese infrastructure financing across smaller littoral states without matching Beijing's Belt and Road capital scale, a genuinely uncertain proposition given the financing gap between the two powers' regional investment capacity.

Diplomatic Positioning

India's diplomatic messaging around its Indian Ocean role has been notably careful to disclaim any Monroe Doctrine-style exclusivity, with officials and strategic commentators explicitly framing MAHASAGAR as cooperative rather than dominant, a positioning aimed at reassuring smaller littoral states wary of trading Chinese influence for Indian hegemony. External Affairs Minister S Jaishankar's participation in successive Indian Ocean Conferences, including the 2025 Oman and 2026 Mauritius editions, and his rhetorical framing of the Indian Ocean as the "Global South Ocean," reflect a deliberate effort to position India's maritime leadership within a broader Global South solidarity narrative rather than a great-power competition frame, a choice that gives India diplomatic room China's more transactional Belt and Road approach does not always afford.

Regional Fallout

Sri Lanka and the Maldives remain the two states where Indian and Chinese maritime influence collide most directly. Sri Lanka has maintained, since at least 2022, a formal position of declining to permit Chinese naval vessels or submarines to dock at its ports, including Hambantota, a commitment India continues to treat with some skepticism given the port's ninety-nine-year Chinese lease and broader debt-related leverage. The Maldives' trajectory under President Muizzu, beginning with an explicit "India Out" campaign and a 2024 Chinese research-vessel port call India's own media characterized in security terms, illustrates how quickly small littoral states can shift alignment, and how limited India's practical tools are to prevent such shifts even when they occur within its traditional sphere of influence. The March 2026 IRIS Dena incident adds a further, distinct layer of regional fallout: Sri Lanka found itself the unwitting site of a major US-Iran military engagement, an outcome with implications for Colombo's own non-aligned positioning and one that further complicates any simple India-versus-China framing of Indian Ocean security dynamics.

Global Strategic Consequences

India's Indian Ocean doctrine, if it succeeds in converting political framework into operational capability, would represent one of the clearer examples of a rising middle power establishing genuine regional security leadership independent of, though not necessarily opposed to, US alliance structures, a model with implications for how other regional powers approach maritime security in contested waters. If it fails to keep pace with Chinese infrastructure and research-vessel expansion, or continues to find itself sidelined by unrelated great-power military action as in the IRIS Dena case, MAHASAGAR risks becoming a well-articulated doctrine without commensurate strategic weight, reinforcing a narrative that India's global ambitions continue to outpace its regional execution capacity.

Risk Matrix

High risk: continued Chinese research-vessel and dual-use infrastructure activity across Sri Lankan and Maldivian waters, testing the practical limits of India's "net security provider" claim without triggering direct confrontation.

Medium risk: further erosion of India's practical influence in swing states like the Maldives if domestic political shifts favor renewed China-leaning governments; continued extra-regional military activity, of the kind demonstrated by the IRIS Dena strike, occurring within India's sphere of interest without Indian consultation or control.

Lower probability but high consequence: a direct India-China naval incident in contested Indian Ocean waters, or a significant escalation in Chinese basing arrangements, whether at Gwadar, Hambantota, or elsewhere, that crosses from ambiguous dual-use infrastructure to explicit military basing, forcing a harder Indian strategic response than the current cooperative-security framing anticipates.

Scenario Analysis

Base Scenario (Medium-High probability): India continues incrementally building out MAHASAGAR's institutional and operational substance, expanding IOS SAGAR deployments, multinational exercises, and Global South outreach, while China continues its own incremental dual-use infrastructure and research-vessel expansion, producing a sustained but manageable competitive equilibrium in which neither side achieves decisive advantage over the medium term.

Bull Scenario (Low-Medium probability): India's naval modernization, including expanded indigenous shipbuilding and blue-water capability, combined with successful MAHASAGAR economic and development outreach, meaningfully outcompetes Chinese influence in swing states like Sri Lanka and the Maldives, consolidating India's net security provider role and giving New Delhi genuine operational, not just rhetorical, primacy across the Indian Ocean Region.

Bear Scenario (Low but non-trivial probability): Continued resource constraints slow India's naval buildout relative to its stated ambitions, a swing state, most plausibly the Maldives or Sri Lanka, moves toward permitting genuine Chinese naval access, and further extra-regional military incidents of the IRIS Dena type occur without Indian involvement or consultation, collectively exposing MAHASAGAR as a doctrine substantially ahead of India's actual regional control.

Intelligence Forecast (6-24 Months)

Over the next six to twelve months, watch for further IOS SAGAR deployment expansion, additional INMSS-2026 operational follow-through, particularly around the doctrine's stated emphasis on emerging technology integration, and any shift in Sri Lankan or Maldivian port-access policy toward Chinese naval or research vessels. Also watch for any Indian strategic or diplomatic response, formal or informal, to the precedent set by the IRIS Dena strike, since continued silence would itself be a meaningful signal about India's practical tolerance for unconsulted great-power military action in its sphere of interest. Over twelve to twenty-four months, the more consequential signal will be whether India's indigenous naval shipbuilding pace, symbolized by the INS Vikrant program, accelerates enough to narrow the capability gap the MAHASAGAR doctrine's ambitions currently imply, or whether resource and industrial constraints continue to leave doctrine ahead of delivered capability. This forecast reflects scenario-based analytical judgment rather than confirmed future developments.

Final Strategic Takeaway

India's evolution from SAGAR to MAHASAGAR, backed by a genuinely more sophisticated 2025-2026 doctrinal and strategic publication cycle, represents the most serious articulation of Indian Ocean maritime strategy New Delhi has produced. The unresolved question is not whether India wants to be the Indian Ocean's primary security guarantor, its rhetoric and diplomatic investment leave little doubt on that point, but whether it possesses, or can build quickly enough, the naval capability and diplomatic leverage over swing littoral states to make that role operationally real rather than aspirational, particularly in a region where both Chinese infrastructure expansion and, as the IRIS Dena incident demonstrated, entirely unrelated great-power military action can occur with limited reference to Indian preferences.

Global Chanakya Assessment

The dominant Indian and Western commentary on Indian Ocean security remains almost entirely framed as an India-China competition, with China's port infrastructure and research vessels treated as the central strategic variable. That framing, while not wrong, has allowed a far more significant data point to pass with minimal strategic scrutiny: the March 2026 sinking of the Iranian frigate IRIS Dena by a US submarine forty nautical miles off Sri Lanka. This was not a China-related event at all, yet it demonstrated more starkly than any Chinese research vessel could that a great power can conduct a lethal military strike inside India's traditional sphere of maritime interest with essentially no reference to Indian awareness, consultation, or consent. A contrarian judgment worth taking seriously: India's MAHASAGAR doctrine, for all its sophistication, may be optimized to compete with the wrong rival. Chinese infrastructure expansion is slow, visible, and diplomatically contestable through the kind of cooperative-security and economic outreach MAHASAGAR is designed to provide; unilateral US military action of the IRIS Dena type is fast, unannounced, and essentially uncontestable by any tool in India's current diplomatic or naval toolkit. The most underreported strategic risk is therefore not Chinese basing ambitions, which India tracks closely and publicly, but the growing normalization of extra-regional powers treating the Indian Ocean as an open military theater for conflicts, Iran-US, and potentially others, that have nothing to do with regional littoral states, a pattern that tests India's "net security provider" claim in ways its current doctrine does not yet address. Key indicators to monitor for how India adapts to this include any post-IRIS Dena changes to Indian maritime domain awareness sharing with the US, any Indian diplomatic statement addressing extra-regional military conduct within the IOR, and whether INMSS-2026's multi-domain operations framework is updated to explicitly account for non-Chinese external military activity.

Implications for India: India's risk is a doctrine-capability gap that becomes visible precisely when it matters most, during an actual crisis rather than a peacetime exercise; its opportunity is that no other regional power currently offers littoral states the combination of cultural affinity, non-exclusive partnership framing, and growing naval capability that MAHASAGAR provides. For Indian foreign policy, the IRIS Dena precedent argues for developing clearer diplomatic tools, short of formal alliance commitments, for engaging extra-regional powers whose military activity intersects India's sphere of interest. For Indian defense planning, sustained investment in indigenous shipbuilding and blue-water capability remains the single clearest lever for closing the doctrine-capability gap. For Indian businesses, MAHASAGAR's Blue Economy and connectivity initiatives across the Global South represent a genuine, if still nascent, commercial opportunity in port development, maritime logistics, and marine sustainability sectors.

Implications for the Global South: African littoral states engaged through MAHASAGAR's expanded outreach, and IORA and BIMSTEC member states more broadly, stand to benefit from genuine Indian investment in capacity building and disaster response cooperation, provided India can sustain the financing commitments its rhetoric implies. ASEAN states watching the IRIS Dena precedent will draw their own conclusions about how much protection regional maritime doctrines, Indian or otherwise, actually provide against unilateral great-power military action within their own waters.

Indicators to Monitor

• Pace and scale of future IOS SAGAR deployments and MILAN exercise participation
• Chinese research-vessel port-access requests and approvals in Sri Lanka and the Maldives
• Any Indian diplomatic or policy response addressing the IRIS Dena precedent and extra-regional military conduct in the IOR
• Indigenous naval shipbuilding milestones, including future carrier and submarine program timelines
• Political developments in the Maldives and Sri Lanka affecting India-China alignment balance
• Updates to INMSS-2026 or successor doctrine addressing multi-domain and grey-zone Indian Ocean competition
• India-US maritime domain awareness and information-sharing agreements
• Chinese basing or port-lease developments at Gwadar, Hambantota, or other Indian Ocean facilities

FAQ

What is MAHASAGAR and how is it different from SAGAR? SAGAR, announced in 2015, framed India's Indian Ocean role around cooperative security and growth within the region. MAHASAGAR, announced in March 2025, extends that framework to the wider Indo-Pacific and Global South, adding an explicit development, sustainability, and technology-partnership dimension alongside security cooperation.

What happened with the IRIS Dena incident, and why does it matter for India? A US submarine sank the Iranian frigate IRIS Dena approximately forty nautical miles off Sri Lanka on March 4, 2026, an entirely US-Iran related event that nonetheless occurred inside India's traditional maritime sphere of interest, highlighting the limits of India's practical control over its own regional waters when extra-regional powers act unilaterally.

Is China building a military base in the Indian Ocean? China's only confirmed overseas military base remains in Djibouti, but analysts have long tracked infrastructure at Gwadar in Pakistan and Hambantota in Sri Lanka as potential future dual-use facilities, alongside a substantial expansion of ostensibly civilian research-vessel activity assessed as serving intelligence and submarine-support functions.

How real is India's naval capability relative to its maritime doctrine's ambitions? India has made genuine progress, including commissioning the indigenously built carrier INS Vikrant, but independent analysts continue to flag a gap between MAHASAGAR's stated ambitions and India's current blue-water capability, particularly relative to the scale of Chinese naval modernization.

What should observers watch for next? The clearest signals are further IOS SAGAR and MILAN exercise expansion, any Indian policy response to unilateral extra-regional military activity like the IRIS Dena strike, and whether Sri Lanka or the Maldives shift port-access policy toward Chinese naval vessels.