Zojila Tunnel: World's Longest High-Altitude Tunnel (13.14 km) at 11,578 ft Achieves Breakthrough, Ensures All-Weather Ladakh Connectivity

Triangular Security Grid Approved for Siliguri Corridor: Garrisons at Dhubri, Kishanganj, Chopra

Home Minister Amit Shah reviewed security of the Siliguri Corridor (Chicken's Neck) and announced a 'Triangular Security Grid' with three new military garrisons at Dhubri (Assam), Kishanganj (Bihar), and Chopra (West Bengal). This is critical for national security as the corridor is the only land link connecting 8 northeastern states to the rest of India.

US-Denmark-Greenland Security Pact Allows Permanent US Basing, Bans Non-NATO Presence in Arctic

The US-Denmark-Greenland security pact, announced on September 18, gives the US permanent basing and overflight rights in Greenland and bars non-NATO nations from building bases or making sensitive investments without US approval. It resolves the NATO strain caused by Trump's annexation demand while preserving Danish/Greenland sovereignty, and remains valid even if Greenland becomes independent. This reshapes Arctic geopolitics amid Russia's military expansion and China's growing footprint.

Subsea Cables Carry 99% Internet Traffic: Vulnerabilities, Ownership Concentration & India's Resilience Plan

Subsea cables carry over 99% of global internet traffic, yet their supply chain is concentrated among a few private players and hyperscalers, making them vulnerable to sabotage, cyberattacks, and economic disruption. Recent NATO, Finland, and China incidents highlight intensifying threats, while India is building repair capacity via a DoT single-window clearance portal. This is a high-yield topic for GS3 infrastructure, science-tech, and security questions.

Trump Threatens NATO Exit, Signs Greenland Security Pact with Denmark

President Trump's threat to leave NATO contradicts his new security pact with Denmark to expand US military bases in Greenland, a territory whose defence is tied to NATO. This creates a strategic paradox that examiners will test for its implications on alliance solidarity, Arctic geopolitics, and US commitment to collective security.

KAVACH Version 4.0 Commissioned on SCR: India’s Indigenous Automatic Train Protection System Explained

KAVACH, India's indigenous Automatic Train Protection (ATP) system, has been upgraded to Version 4.0 and commissioned on the South Central Railway's Malkajgiri–Kamareddi section over 108 route km. This is crucial for UPSC as it touches infrastructure, safety technology, and comparisons with global systems like ETCS, ATC, and PTC. The article also links to Sam Pitroda committee recommendations on railway modernisation.

ONGC to Reserve 50% of 1.75 MMT Mangaluru Storage for Strategic Petroleum Reserves

ONGC will reserve 50% of its 1.75 MMT Mangaluru oil storage facility as strategic storage, while the rest will be used commercially. India's current storage capacity covers 74 days of net crude import requirements, and the government is planning 6.5 MMT more at Chandikhol and Padur. This is a key energy-security move relevant to infrastructure and strategic reserves questions.

Cabinet Approves ₹8,970 Cr, 135.87 km NH-15 Guwahati-Tezpur Corridor with ELF for IAF

The Union Cabinet approved a 135.87 km, ₹8,970 crore Guwahati-Tezpur corridor on NH-15 in Assam, developed on BOT toll mode. It includes an emergency landing facility (ELF) for IAF, five bypasses, and connectivity to 8 PM Gati Shakti economic nodes. This project is a high-yield topic for Prelims data and Mains infrastructure/regional development.

Houthi Capture of Mokha (60 km from Bab-el-Mandeb) Threatens Saudi Oil Routes, East-West Pipeline Shut

Houthi forces seized the strategic port of Mokha (60 km from Bab-el-Mandeb Strait) on September 11, 2026, threatening Saudi Arabia's oil transit via both the Red Sea and the East-West pipeline. This escalation in Yemen's civil war has direct implications for global energy security and Iran's proxy strategy, making it a critical case study for security and international relations exams.