Seoul: South Korea must strengthen surveillance and establish a clear response to repeated North Korean crossings of the military demarcation line (MDL). As North Korea builds roads and positions near the MDL and moves troops closer to the line, some sections of the MDL have become frequent crossing points for North Korean troops.

According to Yonhap News Agency, South Korea's military is considering moving thermal observation devices (TODs) closer to the MDL to determine such instances more accurately, reducing unnecessary warning shots and the risk of miscalculation. This step is necessary, but it raises an unavoidable question. North Korean troops keep crossing the line. Is South Korea's military unwilling to stop them, or unable to?

The problem is that the occurrences are not simply mistakes. North Korea is fortifying the front line, constructing roads and positions, laying mines, and regularly moving troops. Some routes extend south of the MDL, which leads to a pattern: North Korean troops cross the MDL, and South Korean soldiers fire warning shots in response. With Pyongyang effectively seeking to solidify the MDL as a national border, South Korea's military must adjust its response accordingly.

The military's actions so far are concerning. Late last year, a Ministry of National Defense official instructed troops to carefully assess the circumstances when North Korean troops cross the MDL before firing warning shots. Military leaders also allegedly called for soldiers to judge situations individually. Reports of unloaded weapons at frontline posts have also raised suspicions that units have been reluctant to fire warning shots. The more passively South Korea's military responds, the more likely North Korea is to test its defenses. There must be an inquiry into whether avoiding confrontation with Pyongyang has become the top priority.

North Korea recently further formalized its "hostile two state" doctrine by removing references to "peaceful reunification" and "great national unity" from the ruling Workers' Party of Korea's rules. It has also been accelerating its nuclear and missile development. Against such actions, South Korea loosening vigilance along the front line would amount to dismantling its own security defenses.

Moving surveillance equipment northward is not enough. The military must clearly establish that North Korean violations of the MDL will not be tolerated and closely coordinate surveillance and response systems with the United Nations Command. Defense minister nominee Kang Shin-chul should make this issue a top priority after taking office. He must restore military discipline and tighten a weakened readiness posture against North Korea. Security cannot be protected through words or concessions. It requires firm principles and overwhelming response capabilities.