1. Introduction: A Chokepoint Within a Chokepoint

The Strait of Hormuz — a narrow waterway separating Iran from the Arabian Peninsula — has long been studied in geopolitics as the world’s most critical energy chokepoint. Nearly 20% of global oil supply and about 25% of global LNG transits this 33-km-wide strait every single day.

But there is a second, less-discussed layer of strategic vulnerability hiding beneath those waters.

As Iran’s geopolitical tensions with the United States, Israel, and Gulf states have intensified since 2023–2026 — encompassing the Gaza conflict spillovers, IRGC naval confrontations, and threatened Hormuz blockades — the question of deliberate undersea cable sabotage has moved from theoretical to operationally plausible.

For UPSC aspirants, this topic elegantly bridges GS-II (India’s foreign policy, international institutions, geopolitics) and GS-III (critical infrastructure, cybersecurity, digital economy, India’s technology sector).

2. What Are Undersea Internet Cables? The Invisible Backbone of the Internet

The popular imagination associates global internet with satellites. The reality is almost entirely the opposite.

How Submarine Cables Work

• Submarine fibre optic cables are bundles of glass fibres, each as thin as a human hair, sheathed in multiple protective layers.
• They use laser pulses of light to transmit data at speeds close to the speed of light — typically hundreds of terabits per second on a single cable.
• Cables are laid by specialised cable-laying ships and anchored to the seabed, often in trenches or buried in shallow coastal zones.
• Repeaters are embedded every ~100 km to amplify signals across thousands of kilometres of ocean.
• As of 2026, there are over 570 active submarine cable systems spanning more than 1.4 million km of ocean floor globally.

Historical Cable Cuts and Their Impact

• 2008 — Mediterranean cable cuts: Four cables cut near Egypt disrupted 70% of internet traffic between India and Europe; India’s international bandwidth dropped by ~60% for weeks.
• 2022 — Tonga volcanic eruption: One cable cut left Tonga almost completely isolated for 5 weeks.
• 2024 — Baltic Sea cables: Two cables damaged near Finland and Sweden amid suspected Russian involvement, triggering NATO alert.
• 2024 — Red Sea cables: Houthi attacks and maritime instability caused damage to the AAE-1, Seacom, and EIG cables — directly impacting India, impeding 25% of Asia–Europe traffic.

3. Why the Strait of Hormuz Is Critical for Global Internet

The Persian Gulf, Gulf of Oman, and waters surrounding the Strait of Hormuz host some of the world’s most strategically important submarine cable corridors.

Major Cable Systems in the Region

A coordinated attack on even 3–4 of these cables in the Gulf region would cause unprecedented global data disruption on the most trafficked internet corridor on earth.

4. What Happens If Iran Cuts Internet Cables? A Phased Impact Analysis

🔴 Immediate Impact (First 24–72 Hours)

• Internet outages and slowdowns across South Asia, Middle East, East Africa, and parts of Europe — particularly for services dependent on affected cable routes.
• Automatic rerouting by internet service providers (BGP rerouting) will push traffic to alternate cables — but this takes hours and significantly increases latency and packet loss.
• Video conferencing, cloud applications, OTT streaming, and VoIP will degrade sharply.
• Stock exchanges and algorithmic trading systems that depend on low-latency fibre connections will experience millisecond disruptions with potentially large financial consequences.
• Data centres in UAE, India, and Europe handling multi-region traffic will see congestion.

🟠 Medium-Term Impact (1 Week to 3 Months)

• Cloud service disruptions: AWS, Google Cloud, Microsoft Azure all have region-specific traffic that depends on Gulf-adjacent cables. India-hosted cloud zones would experience partial isolation.
• Financial transaction delays: SWIFT, international banking settlements, and cross-border payment systems would slow — affecting global trade finance.
• Stock market volatility: Technology stocks, telecom companies, and cloud providers would see sharp selloffs. Oil markets would simultaneously spike due to the dual Hormuz shock.
• IT companies dependent on real-time data access across continents would lose productivity.
• Satellite backup capacity (Starlink, VSAT) would be overwhelmed — satellite internet cannot absorb the global cable load (too low bandwidth, too high latency for financial systems).

🔵 Long-Term Impact (3 Months to 5 Years)

• Accelerated diversification of global cable routes — new investments in Cape of Good Hope routes, Arctic Cable corridors, and Pacific alternatives.
• Geopolitical tech competition will intensify — the US, China, India, and the EU will all invest in state-backed cable infrastructure.
• Increased demand for Low Earth Orbit (LEO) satellite networks (Starlink, OneWeb, Amazon Kuiper) as strategic backup.
• International legal pressure to designate submarine cables as protected critical global infrastructure under UNCLOS and UN frameworks.
• Insurance premiums for cable operators and telecom companies with Gulf exposure will surge.

5. Global Impact: Who Gets Hit Hardest?

Cables through the region carry the largest volume of data traffic between Europe, Asia, and Africa — disruption would be asymmetric but universal.

The Double-Shock Scenario

6. 🇮🇳 Impact on India — The Core UPSC Section

India’s internet depends heavily on submarine cables passing through the Arabian Sea and Gulf region. This makes India one of the most geographically exposed major economies to a Hormuz cable disruption.

6.1 Internet Connectivity and Telecom

India currently has over 200 submarine cable systems touching its shores — with major landing points at Mumbai, Chennai, Cochin, and Tuticorin. The vast majority of India’s international bandwidth transits routes through the Arabian Sea toward the Gulf.

• A Hormuz disruption would force rerouting through Pacific cables — increasing round-trip latency from ~80ms (India–Europe) to 200ms+ (Pacific re-route). For real-time applications, this is a catastrophic degradation.
• Mobile data speeds for international content (YouTube, Netflix, Instagram, WhatsApp calls) would slow dramatically.
• India’s 80 crore+ internet users would experience the impact directly.

6.2 Banking, UPI & Digital Economy

• India processes over 13 billion UPI transactions per month — while UPI itself is a domestic system, the underlying data infrastructure, cloud hosting, and international financial connectivity are cable-dependent.
• Stock markets (BSE, NSE) rely on international settlement systems and foreign institutional investor activity that depends on low-latency cable links.
• International SWIFT transactions — used for trade finance, remittances from Gulf countries (India receives $30+ billion annually in Gulf remittances) — would face delays.
• Fintech unicorns and neobanks with global operations would face partial operational paralysis.

6.3 IT and BPO / Outsourcing Sector

• India’s IT sector exports exceed $250 billion annually, with clients primarily in the US and Europe. Service delivery depends on real-time, low-latency cable connectivity.
• Cloud-based development (AWS, Azure, GCP deployments in India regions) would be partially impacted — particularly multi-region deployments and Europe-hosted client data.
• Major IT hubs — Bengaluru, Hyderabad, Chennai, Pune — would see productivity losses from degraded international network performance.
• SLA (Service Level Agreement) breaches could trigger financial penalties for Indian IT firms.

6.4 Strategic and National Security Dimensions

• India’s dependence on foreign-controlled cable infrastructure represents a strategic vulnerability that has no quick fix.
• Military communications rely on secure fibre links — degraded connectivity between Indian command centres and overseas assets (like ONGC Gulf platforms) creates operational risks.
• India’s 3.4 million Gulf diaspora would be affected by communication disruptions and remittance delays.
• India’s energy diplomacy (oil imports from Iran, UAE, Saudi Arabia) would be impeded by communication infrastructure failure at the same moment as the energy crisis intensifies.

7. Economic Impact: When Digital and Energy Crises Collide

The economic consequences of a Hormuz internet cable disruption cannot be analysed in isolation from the simultaneous energy shock.

Financial Market Volatility

• Oil price spike (Brent Crude potentially touching $120–150/barrel) combined with internet disruption would create simultaneous inflationary and deflationary shocks across global markets.
• Technology stocks (Big Tech: Apple, Meta, Google, Microsoft) would fall sharply as cloud and advertising revenue models depend on global internet infrastructure.
• Telecom companies with submarine cable exposure (SoftBank, Tata Communications, BSNL) would see regulatory and operational crises.
• Insurance companies underwriting cable infrastructure would face massive liability exposures.

Global GDP Impact

• Historical modelling suggests a complete disruption of Asia–Europe cables for 30 days could cost the global economy $10–15 billion per day in lost productivity, delayed transactions, and inefficiency.
• Developing nations disproportionately dependent on Gulf cable routes — India, Pakistan, Bangladesh, Kenya, Ethiopia — would suffer longer-term economic setbacks.

8. Military & Cybersecurity Dimension

Hybrid Warfare and Grey Zone Operations

The targeting of submarine cables is a classic instrument of hybrid warfare — actions that fall below the threshold of conventional armed conflict while causing disproportionate strategic damage.

• IRGC (Islamic Revolutionary Guard Corps) Navy has the maritime capability — submarines, remotely operated vehicles, and combat divers — to physically cut or damage cables in the Gulf.
• The challenge of attribution (proving deliberate sabotage vs. accidental damage by ships’ anchors) provides Iran with plausible deniability.
• Russia’s use of cable sabotage in the Baltic (2024) has established a dangerous precedent that other actors are watching carefully.

Cyberattack Amplification

• Physical cable disruption creates windows of increased cyber vulnerability — rerouted traffic through less-secure alternate paths can be more easily intercepted or manipulated.
• State-sponsored cyber actors could exploit the disruption period to conduct espionage, inject malware, or disrupt financial clearing systems.
• Critical infrastructure attacks (power grids, water systems, hospitals) during the disruption window become more feasible as SCADA systems lose remote monitoring capabilities.

9. Can the Internet Be Completely Shut Down?

A nuanced understanding here is critical for UPSC answers — and for avoiding oversimplification.

Why a Complete Shutdown is Unlikely

• The internet was architecturally designed (originally as ARPANET) for resilience and redundancy — to route around damage.
• There are multiple cable routes between continents; cutting one or even several triggers automatic rerouting via BGP (Border Gateway Protocol).
• Satellite backup (Starlink LEO constellation: 5,000+ satellites), VSAT, and terrestrial overland fibre routes provide partial fallback.

Why the Impact Would Still Be Catastrophic

• Rerouting through longer paths significantly increases latency — making real-time applications (video, finance, gaming) unusable.
• Alternate cable routes do not have the capacity to absorb the full traffic of disrupted Gulf cables — resulting in severe congestion even if connections nominally persist.
• Satellite internet capacity is insufficient for enterprise-grade, financial, or military applications requiring microsecond precision.
• The economic and psychological impact of degraded internet is nearly as damaging as a full outage in the modern digital economy.

10. Solutions and Way Forward

For Global Governance

• UN Convention on Submarine Cable Protection: Extend UNCLOS protections to actively designate submarine cables as protected international infrastructure akin to civilian hospitals in conflict zones.
• Establish a UN Cable Protection Task Force to monitor and respond to sabotage events — similar to IAEA for nuclear safeguards.
• NATO and Quad-level agreements for joint cable protection patrols in strategic choke points.

For India’s Digital Resilience

• Cable Route Diversification: India must invest in cable routes bypassing the Gulf entirely — including southern African routes (via Cape of Good Hope) and potential Central Asian overland fibre.
• Acquire Cable Repair Vessels: India currently has no domestic cable repair ship capacity. BSNL and DoT must establish this strategic asset.
• Satellite Backup: Accelerate indigenous LEO satellite development (ISRO’s Space Dock initiative) and negotiate Starlink/OneWeb strategic access for emergency backup.
• Data Localisation Strategy: Encourage hyperscalers (AWS, Google, Microsoft) to expand India-based data centres and local content delivery infrastructure to reduce dependence on international cables for domestic traffic.
• National Submarine Cable Policy: India must develop a dedicated Submarine Cable Policy under DoT/MoCI with mandatory redundancy requirements for international telecom operators.
• Gulf Relations: Diplomatically, India’s “Act West” policy must explicitly include digital infrastructure agreements with UAE, Oman, and Saudi Arabia for mutual cable protection.

11. UPSC Prelims — Quick Revision Points

12. UPSC Mains — Model Answer

13. Frequently Asked Questions (FAQ)

Conclusion: The Invisible Front Line

The global internet’s invisible backbone — 1.4 million kilometres of submarine cables resting on ocean floors — is simultaneously the world’s most critical and most vulnerable infrastructure. As geopolitical competition intensifies in maritime corridors like the Strait of Hormuz, the deliberate targeting of this infrastructure has moved from a theoretical possibility to a credible strategic instrument.

For India, the stakes are particularly high. A nation of 1.4 billion people, an $4 trillion economy, and the world’s fastest-growing digital market cannot afford strategic complacency about the handful of submarine cables connecting it to the global economy. Diplomatic engagement, domestic capability building, route diversification, and international legal architecture must all advance together.