Silent Threat, Loud Warning: Why India’s Submarine Gap Matters After the US-Iran Naval Strike

The reported torpedo strike by a US submarine that sank an Iranian warship near Sri Lankan waters has brought submarines back into sharp global focus. Described as a “quiet death,” the incident underscores a fundamental truth of modern naval warfare—dominance beneath the surface often determines control above it.

While the strike occurred far from India’s immediate conflict zones, it has triggered renewed scrutiny of the Indian Navy’s own underwater capabilities—an area where ambitions have long outpaced execution.

The Strategic Power of Submarines

Submarines are among the most potent assets in naval warfare. Their stealth, endurance, and ability to strike without warning make them critical for deterrence, intelligence gathering, and sea denial.

The recent US action demonstrates how a single submarine can alter the tactical equation in contested waters without ever being detected—highlighting why undersea strength is a cornerstone of maritime power.

India’s 30-Year Submarine Plan: Falling Short

India’s long-term submarine development strategy, launched in 1999, envisioned a fleet of 24 submarines by 2030, including six nuclear-powered attack submarines. However, as the deadline approaches, progress remains significantly behind schedule.

To date, only six Kalvari-class (Scorpene) submarines have been inducted under Project-75. This falls well short of the planned expansion and leaves critical gaps in India’s underwater combat capabilities.

Currently, the Indian Navy operates 19 submarines—16 conventional, two nuclear-powered ballistic missile submarines (SSBNs), and one nuclear-powered attack submarine on lease. Many of the conventional submarines are aging, with several nearing three decades in service.

Project-75 (India): A Crucial Yet Complex Step

To address capability gaps, India is moving forward with Project-75 (India), which aims to build six advanced conventional submarines equipped with Air Independent Propulsion (AIP) technology. This will allow submarines to remain submerged for longer durations, significantly enhancing stealth and operational reach.

German defense major ThyssenKrupp Marine Systems (TKMS) is a leading contender for the project, with plans to collaborate with an Indian shipyard to manufacture the submarines domestically.

The initiative is not just about acquiring platforms—it is central to India’s broader goal of strengthening indigenous defense Manufacturing and reducing long-term dependence on foreign suppliers.

Concerns Over Procurement and Industrial Balance

Despite its strategic importance, Project-75 (India) has raised several concerns within defense and industry circles. One major issue is the limited competition that emerged during the bidding process, partly due to the program’s complex technical and procedural requirements.

Another key debate revolves around the balance between foreign expertise and domestic participation. While foreign partners bring critical design and technological capabilities, excessive reliance on them could limit the growth of India’s own submarine design and engineering ecosystem.

There are also questions regarding Early Work Agreements (EWAs), which allow preliminary design and planning activities before final contracts are signed. While these agreements can accelerate timelines, they may also reduce cost transparency and weaken negotiation leverage if not carefully structured.

Strategic Stakes in a Changing Maritime Landscape

India’s submarine gap must also be viewed in the context of rising maritime competition in the Indo-Pacific. Both china and Pakistan are steadily expanding their naval capabilities, including undersea fleets.

In such an environment, submarines are not just tactical tools but strategic assets essential for maintaining credible deterrence and safeguarding sea lanes.

The Way Forward: Capability and Self-Reliance

The lesson from the recent US-Iran naval episode is clear—undersea warfare remains as decisive today as it was in the past, if not more so. For India, bridging the gap between planned and actual submarine strength is no longer optional but imperative.

Moving forward, success will depend on ensuring transparency in procurement, fostering meaningful technology transfer, and strengthening domestic industrial participation. These factors will determine not only the Navy’s operational readiness but also India’s long-term strategic autonomy in submarine design and construction.

Ultimately, the challenge is not just to build more submarines, but to build the capability to design, produce, and sustain them independently—ensuring that India remains a formidable maritime power in an increasingly contested region.