A South Korean soldier stands at an OP just south of the DMZ, with North Korea in the distance in this 2018 photograph. Last week, in the early hours of February 16, a North Korea swum through freezing seas, infiltrated coastal defenses and crossed the beach below this observation post. Photo: Asia Times/Andrew Salmon

“The bomber will always get through,” said British parliamentarian Stanley Baldwin in 1932, in a stark warning about the fallibility of defenses.

Substitute “infiltrator” for “bomber” and this may be the argument South Korea needs to hear after the country’s Demilitarized Zone, or DMZ, defenses were breached yet again last week when a North Korean made it over the highly sensitive frontier.

Despite the near-superhuman physical hardiness and determination displayed by the man, who made landfall in the South on February 16 after an extraordinary crossing, South Korea’s chattering classes – some of whom evince neither trust nor respect their military – are lambasting it for a perceived failure of systems and personnel.

Yet, one expert said, the army did succeed in its mission. It captured the North Korean within hours, and before he could reach a civilian area.

Moreover, those with related experience say that against toughness and resourcefulness it is impossible to completely secure the DMZ.

South Korean marines patrol on the South Korea-controlled island of Yeonpyeong. Photo: AFP/Yonhap

The fortified frontier

Most reportage of the DMZ – particularly TV reports and press photography – cover Panmunjom, the iconic truce village set inside the DMZ. However, that strictly organized space – which can even be visited by tourists – is a world away from the “real” DMZ.

The Demilitarized Zone is a four-kilometer wide strip of land that has bisected the waist of the Korean Peninsula since 1953, the year the Korean War halted uneasily. It is one of the most dangerous flashpoints on earth.

In the absence of development, it is an overgrown, rugged space alive with wildlife. The only humans who visit are troops from both sides – and even they stick to patrol routes and small positions on their respective sides of the Military Demarcation Line (demarcated by white fence posts) – the actual border inside the DMZ.

No weapons heavier than machine guns are permitted inside the DMZ. But the adjacent areas north and south bristle with heavy weaponry.

Behind the razor wire-topped, chain-link fences on the southern side of the DMZ, strongpoints, artillery concentrations and infantry bases are impossible to miss, even for the casual driver or hiker.

Minefields, razor-wire fences, and observation posts present physical obstacles to any seeking to cross the zone. Infantry – often equipped with binoculars, sniper optics and night-vision goggles – roam. Ground sensors, ground radars, networks of security cameras rigged to alarms, infra-red cameras, heat-seeking cameras and searchlights that light up after dark keep the area surveilled, 24/7.

Given the huge risks presented by these barriers, it is hardly surprising that the vast majority of the 33,752 defectors who have reached South Korea did so after crossing into China, rather than risking the DMZ.

But since Covid-19 struck last year, North Korea has also sealed off its China border, deploying elite units to supplement border guards.  As a result, only 229 defectors made it to the South in 2020. The number had been more than a thousand in each of the previous five years.

In this situation, the DMZ provides an option for the desperate – or the highly motivated. It is not clear which of these last week’s infiltrator was – but it is clear that he undertook an epic task.

South Korean soldiers patrol along a barbed wire fenced area of the Demilitarized Zone. Photo: AFP

Seaborne infiltration – in midwinter

Though many details about the recent breach remain murky, and no photos have been released, considerable information is now known. Seoul’s Joint Chiefs of Staff released the result of a probe into the incident, and spoke to media on Tuesday while the Defense Minister was grilled in the National Assembly.

A North Korea man in his 20s crossed into the South on February 16. Instead of infiltrating through the terrestrial DMZ, he crossed the East Coast maritime frontier via a six-hour, night-time swim in sub-zero temperatures and rough seas.

The infiltrator was identified as a fishing industry worker, and professional knowledge may have aided him: currents at his time of crossing were running north-south.

He was wearing an old-fashioned dry suit, of the kind used by hard-hat divers of the past, some of whom still operate on the east coast. Underneath, he was wearing thick clothes as insulation, the JCS said.  

The coast just south of the DMZ is overseen by the same kind of defenses seen on land.

Beaches are cordoned off with high fences topped with razor wire and search lights, intersected by guard posts. The area from the surf line to 500 meters to seaward is the responsibility of the army. Beyond that, it is the responsibility of the Coast Guard and Navy.

After making landfall at 01:05AM, the man crossed the beach and made his way inland by crawling through a drainage culvert under the fencing.

Once inside the fence line, he headed south for four hours, before being spotted on security cameras at 04:16AM. A manhunt was initiated and he was confronted by a patrol at 07.27AM.

Captured, he announced his intent to defect. He was carrying no espionage-related equipment, the South Korean military said.

A North Korean infiltration submarine captured in 1996, stands in stark contrast to the bunker in the background – an active duty east coast fortification manned by South Korean troops. Photo: Asia Times/Andrew Salmon

Military under fire

What has incensed South Korea is that the man bypassed so many barriers.

According to the JCS investigation, he triggered 10 camera alarms but troops monitoring the cameras only responded to two. One soldier who should have seen the man was working on a computer, another was engaged in a phone conversation and yet another misidentified him as a South Korean officer returning home, reports said.

“Service members in charge of the guard duty failed to abide by due procedures and failed to detect the unidentified man,” the JCS said.

It has also emerged that the drain through which the defector made it inland was not blocked off with a grid or bars, even though a North Korea re-defected to the North last year by passing through a similar pipe last July.

Moreover, a boatful of North Koreans made it past South Korean defenses in 2019, and last November, a defector crossed the DMZ – reportedly by using gymnastic skills to bypass border fencing.

Not only are there perceived failings in these cases, many South Koreans – who retain bitter memories of the military governments that ruled their country from the 1960s to the 1980s – are highly critical of their uniformed services.

Many refused to believe that a North Korean submarine sunk the South Korean corvette Cheonan in the Yellow Sea in 2010, killing 46 sailors. Rampant rumors spread that the disaster was an internal accident, or fratricide. Some alleged that the navy forged evidence of the North Korean torpedo.

In 2014, the Coast Guard was the target of massive public fury after over 300 lives were lost during the Sewol ferry tragedy in 2014 – even though the ship’s hapless crew had ordered passengers to remain below decks as the vessel foundered.

The media is in attack mode.

The conservative Joongang Ilbo, Korea’s second largest-selling newspaper, opened fire with both barrels.  The situation was “an example of how our military is disorganized,” the newspaper alleged in a February 18 editorial.

The paper pointed the finger at poor training, but also put the boot into the Moon Jae-in administration’s enthusiasm for engaging North Korea. “This is the result of the administration shouting ‘peace,’” the paper thundered.

But anti-infiltration defense is no easy matter – and many civilians are unfamiliar with operational realities.

Toy soldiers from north and south at a DMZ museum gift shop. The real things are not far away, but while North Korea has massive respect for its army – as witness the many parades held in the capital – many in the South are critical of their forces. Photo: Asia Times/Andrew Salmon

DMZ: Defensible but permeable

A recently retired soldier familiar with frontline DMZ defense – albeit in a different part of the border – told Asia Times that human error is not just likely but almost inevitable.

Referring to camera-triggered alarms, he said, “Those alarms used to go off two-three times per day.”  When that happens, soldiers are dispatched to the scene, but laxness is almost a given.

During the source’s 21 months of conscript military service, 99% of alarms were triggered by wildlife, he recalled; the other 1% were triggered by wind. No North Korean was caught or even sighted, the source added.

Another retired soldier – though one far higher up the command chain – made clear that the military had, in fact, succeeded.

“The DMZ is a defense line against large formations of tanks and troops, it is 155 miles wide,” Chun In-bum, a retired major general who formerly headed South Korea’s Special Warfare Command told Asia Times.

When it comes to small units or civilians, “it’s hit or miss,” Chun said. “Sometimes we get them, sometimes we don’t, but the goal is to get them before they reach a significant civilian population.”

As the man was captured inside the Civilian Control Zone” – a cordon sanitaire several kilometers south of the DMZ, where civilian access is restricted – the South Korean troops had, in fact, succeeded.

It is impossible to say whether or how many enemy agents have infiltrated, undetected, across the DMZ. However, it is widely assumed that some of the 33,000 North Koreans who have escaped to the South, usually via third countries, are deep-cover agents posing as defectors.

Regarding the recent infiltration Chun, who commanded troops during a massive manhunt after a submarine-based infiltration in 1996, did raise one eyebrow.

“If he is a true blue fisherman, I am a little concerned with the reporting that this guy was hidden under some leaves when they found him,” Chun said. “That is usually what a military guy would do – how would a civilian know to warm himself under dead leaves? That technique is not generally known.”

Meanwhile, a totally secured border is a chimera.

“It is not a 100% effective system,” said the former conscript. Any hopes for such efficiencies do not make sense, he said. 

Given this, the military should not over-promise.

 “The Korean military have been boasting for the last 70 years that we can do it 100% but nobody – not the Americans, not the Chinese – can do it 100%,” Chun said. “It is time the Korean military was honest about this and the civilians understood it.’

Upgraded border security would require massive deployments of troops and cash. “If the public want 100% we need to put 100,000 or 200,000 more men on the border and invest a couple of hundred million dollars,” Chun said.

Given the non-likelihood of that, there will be future breaches. “This won’t be the last time,” said the retired general. “Let me assure you of that.”

Binoculars overlooking the DMZ, from the South. Photo: Asia Times/Andrew Salmon