NexDef Analysis | South Koreaโs Military Modernisation โ Land, Sea, Air & Industry
South Korea is no longer just a high-end buyer, it is moving into the category of developer-exporter of military systems. With a defence budget target of about 66.3 trillion won (~US$47 billion) in 2026, up ~8.2% from prior year, Seoul is doubling down on advanced technologies, long-range deterrence, and domestic industrial capacity.
The rationale: a nuclear-armed North Korea, increasingly capable adversaries, and the need to reduce dependency on foreign suppliers while positioning for exports. South Korea already ranks among the worldโs top 10 defence spenders and is the worldโs 8th largest arms exporter.
Land. Ground forces modernisation focuses heavily on artillery, armoured systems, and networked integration for high-intensity combined arms. For example, the K9 Thunder self-propelled howitzer is being upgraded to the K9A3 with a target range >100 km using gliding munitions. The ROK Army is also expanding mechanised brigades, introducing new IFVs and upgrading legacy platforms. This pivot signals the shift from merely holding ground to projecting ground-force fire-power deeper, faster, and more precisely.
Air. The air domain is at the core of Seoulโs ambition. The indigenous KFโ21 Boramae jet (initially 4.5 generation, with path to full stealth Block-II) is in serial production, from 2026 delivery onward, with about 120 units planned by 2032. Together with expanded acquisition of F-35As and enhancements to IAMD (Integrated Air & Missile Defence), South Korea is building layered air-power and deterrence. Space and surveillance are also part of the equation: Koreaโs first domestically-built military spy satellite launched via SpaceX in 2023 underscores push for autonomous ISR.
Sea & Undersea. Maritime modernisation is robust, including the diesel-electric/slash-SLBM-capable KSSโIII submarine programme (Dosan Ahn Chang-ho-class) and new surface combatants geared for blue-water and littoral roles. In the face of regional submarine proliferation (including North Koreaโs and Chinaโs), Seoul is investing in both deterrent sea-denial and exportable shipbuilding.
Industry & Exports. Perhaps the most significant shift is industrial: South Korea is targeting defence exports of >US$10 billion annually and aiming to become one of the top four arms exporters by 2027. Domestic firms such as Hanwha Aerospace and Korea Aerospace Industries (KAI) are winning export orders: for example, KAI signed ~US$712 million deal to supply FA-50 fighter jets to the Philippines. The acquisition framework itself is being reformed: Seoul is adopting rapid acquisition models and commercial-tech integration to speed fielding of AI, unmanned systems and dual-use tech.
South Koreaโs modernisation is structured around three interconnected pillars: capability, autonomy, and export credibility.
Capability: The budget increase and system launches reflect an understanding that Seoul must assume readiness for high-intensity conflict (not just border skirmishes). Range (air, artillery, missiles), stealth (KF-21), undersea denial (KSS-III) and ISR autonomy (satellite, drones) all coalesce into a credible deterrent.
Reliance on external suppliers (notably the U.S.) is being reduced. Indigenous development warrants technology control and sovereignty. The KF-21 programme, for example, intentionally domesticises radar, EW and propulsion to avoid export/trade constraints.
By selling abroad, Korea earns economies of scale, technology maturation and geopolitical influence. A strong export track builds industrial resilience and finances domestic R&D. But this creates risks: global competition, dependence on exports for sustainment, and pressure to prioritise export spectrums over purely national needs.