North Korea watcher Jacob Bogle has analysed satellite photos of North Korea’s naval bases – including one close to one of Kim Jong-un’s homes – and claims there is a crucial flaw in their design
North Korea's hidden underground naval bases have been exposed in these satellite images which reveal "one giant weakness" in their defences, an analyst claims.
Amid a fresh outburst of aggression from the Kim regime, US-based analyst Jacob Bogle has probed the North’s navy using photos available to the public.
His research revealed more than a dozen subterranean maritime facilities which the dictatorship can use to repair and refuel warships, as well as launch attacks, in safety and secrecy.
The bases – one of which is less than a mile from a private Kim Jong-un residence – also offer a place to shelter from enemies, but Mr Bogle claims they have a crucial flaw.
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“Kim Jong-un has invested huge sums of money in modernising the country’s conventional forces and related facilities,” he said.
“Improvements to their naval assets have already been seen across the country.
“But all underground facilities have one giant weakness: their entrances. Destroy those and whatever is inside becomes useless.”
Given North Korea’s attempts to develop submarine-launched nuclear missiles, the significance of these bases could be enormous if war broke out, Mr Bogle said.
“Unlike the US or UK, which only have a few submarine-related bases – none of them underground – the fact that North Korea has so many creates added challenges for any preemptive strike,” he said.
“It would require a near simultaneous attack on all of the bases to confidently knock out their submarine capability.
“Otherwise some vessels may escape and go on to threaten any adversarial forces in the area.
“Additionally, North Korea intends to build a submarine fleet capable of firing nuclear weapons – submarine-launched ballistic missiles (SLBMs).
“Knowing where those submarines are housed prior to any future attack would be paramount.”
In images collected by Mr Bogle, several navy bases can be seen to have waterways leading from the sea and into tunnels.
While the exact scale of the tunnels is unknowable, some of them appear to have two access points, allowing us to draw a line between the exit and entrance to reveal the tunnel’s potential size.
“One cannot tell by looking at commercial satellite imagery how complicated their interiors are,” said Jacob.
“Do they have multiple side channels and galleries, for example?
“But it is likely that at least some of the larger bases contain more than a single, narrow tunnelway within its respective mountain.”
It’s also possible that another submarine base at Changjon, close to the South Korean border, could be brought back into action.
It was closed during a period of co-operation between North and South, but now the two are at odds again, with Kim Jong-un blowing up a shared building in the border town of Kaesong on Tuesday.
“As relations have deteriorated, that base's strategic and propaganda value has grown,” said Jacob.
“North Korea has destroyed the liaison office in Kaesong and committed to moving their military back into these demilitarised areas.
“So there is a chance that the underground submarine base at Changjon could see reactivation sooner than expected.”
Mr Bogle, who has created a comprehensive map of North Korea from satellite images, said the bases “were constructed several decades ago”.
“We know that they at least meet the level of sophistication found in other similar bases around the world during the 1960s and 1970s,” he said.
“And imagery suggests that some entrances may have blast doors for defence as well as a system of devices to detect the presence of enemy submarines trying to infiltrate the base harbour.”
North Korean submarines are outdated, Mr Bogle added, but he believes they remain a real danger to neighbouring countries.
“North Korean submarines certainly are not a direct threat to the US,” he said.
“They rely on old diesel engines and propulsion systems and thus they are limited in how long they can stay submerged, and they are relatively noisy compared to modern submarines.
“Their primary threat currently is to South Korea and possibly Japan.
“In a war, North Korea plans to use submarines to harass shipping routes – the value of South Korean routes is over $1 trillion – and to enable the infiltration of special operations forces.
“Since their submarines can float in and out of hidden bases, their movements are harder to monitor and would pose a real threat to South Korea.
“That threat only grows as Pyongyang’s SLBM development progresses.”
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