South Korea’s Ministry of National Defense announced plans to reduce the number of troops stationed near the demilitarized zone (DMZ) from approximately 22,000 to 6,000 by 2040, a nearly 75 percent cut. This strategy is aimed at addressing the ongoing decline in military personnel and involves replacing much of the front-line human presence with advanced surveillance technologies, including artificial intelligence (AI), multi-legged robots, and drones.

Defense Minister Ahn Gyuback emphasized the necessity of this shift in light of demographic challenges, stating that maintaining a traditional manpower-heavy border security system is no longer feasible as South Korea faces a shrinking pool of eligible soldiers due to its low birthrate. The Defense Ministry plans to gradually phase in enhanced surveillance equipment starting in 2027, creating a more technology-driven operational framework.

However, the proposal has drawn criticism, chiefly from opposition lawmakers who argue that reducing troop numbers along the heavily fortified border with North Korea could undermine national defense and exacerbate public concerns. Han Ki-ho, a member of the opposition People Power Party, warned that cutting guard troops without ensuring adequate surveillance capability might increase anxiety over security.

Experts also voice concerns about the operational impact of such a reduction. Park Won-gon, a professor specializing in North Korean studies, noted that front-line troops are not only essential for monitoring North Korean activity but are also the initial combat forces to respond in case of conflict. Reducing these units could weaken South Korea’s readiness, particularly given recent provocations from the North, including incursions across the military demarcation line and ongoing missile tests.

The planned troop reduction does not hinge on reciprocal action from North Korea, which raises questions about whether South Korea might face a strategic disadvantage as Pyongyang continues to pursue more aggressive military postures. Park pointed out that North Korean leader Kim Jong-un has reaffirmed territorial ambitions toward the South, suggesting the possibility of increased military pressure.

The potential weakening of South Korea’s front-line defense capabilities also intersects with broader security dynamics involving the United States. While U.S. Forces Korea (USFK) remains committed to its peninsula defense mission, there are indications of an expanded role in the broader Indo-Pacific strategy. Analysts suggest that Washington prefers Seoul to maintain robust self-defense capabilities, though the U.S. may recognize South Korea’s manpower challenges as somewhat unavoidable.

From a strategic standpoint, incorporating AI and other advanced technologies could help South Korea modernize its defenses and reinforce efforts to assume greater wartime operational control, a key goal for Seoul’s military. Senior research fellow Kim Jong-sup from the Sejong Institute highlighted the importance of accelerating technological integration to maintain effective defense amid personnel declines.

Nonetheless, some experts remain skeptical about the extent to which AI and robotic systems can fully replace human soldiers on the challenging terrain of the Korean border. Yang Uk, a national security researcher, commented that mobile robotic platforms still face significant limitations and that fixed AI-equipped systems may not be sufficient to replicate the range of duties performed by troops.

South Korea’s armed forces have seen active service numbers fall from 560,000 in 2019 to about 450,000 in 2025, a trend expected to continue. Projections suggest the pool of military-eligible men could shrink further by 2039, intensifying the strain on recruitment and operational effectiveness. The Defense Ministry’s plans signal a strategic pivot toward technology-driven border defense, but the transition raises pressing questions about maintaining readiness in one of the world’s most volatile security environments.