I'm not concerned about North Korea's military (and don't think anyone should be unless professionally obliged to or obliged to pay taxes in South Korea). It's nevertheless an interesting case study.
North Korea's military was built up with foreign help and WW2 vintage equipment within a few years, and became capable of independent warfare in only half a decade.
By mid-1950 North Korean forces numbered between 150,000 and 200,000 troops, organized into 10 infantry divisions, one tank division, and one air force division, with 210 fighter planes and 280 tanks [...]
That is in itself astonishing. Keep in mind that North Korea was not exactly rich in car mechanics or even aircraft mechanics, despite being the more industrialised half of Korea.
- - - - -
|Korean War map, (c) apparently "Roke"|
North Korea overran South Korea's defences in June-July 1950 with superior (light) infantry on the hills/mountains and superior WW2 vintage T-34/85 tanks in the valleys.
The latter were mostly lost and the former was badly decimated when the last South Korean troops and foreign intervention troops defended the area at Pusan.
The details of these battles would make most interesting fodder for this blog post, but I'll abstain because that kind of stuff would only lead to stupid "anti-Americanism" charges and almost nobody would believe me anyway. So whoever is interested; look this stuff up elsewhere, preferably in a non-American and non-Korean source.
The long story short is that North Korea's infantry divisions had already lost most of their combat troops and were defending successfully against numerically and even more so materially superior foreign force with a tactical offence that included heavy use of infiltration tactics. The whole episode was thoroughly amazing and -to some- thoroughly embarrassing.
(Keep in mind that Western-style divisions of the time and even nowadays had up to 1/4th of their troops allocated as drivers of motor vehicles and unavailable for night-time rifle combat!)
Eventually the Inchon landing turned the front-line and the exhausted North Korean military was on the run till the red Chinese intervened and pulled off the whole "superior light infantry on hills/mountains + infiltration attacks" routine anew, with similar results.
The 'hot' war finally ended and the whole deadlock mess became part of the then Cold War.
- - - - - -
Afterwards, North Korea still had a strong claim for being a very proficient opposing force in Korean terrain (not much unlike Italian geography), and this seemed to suffice for a while.
The Cold War finally ended sometime around '86 to '92, and North Korean leadership had to realise that its deterrence was deprived of the PRC's nuclear umbrella, the whole Cold War mutually assured destruction insanity and on top of that North Korea wasn't able to keep up with military technology advances.
The critical weakness was in my opinion about night vision devices (the near infrared passive low light goggles). The Soviet Union had slept over this development and was lagging in military modernisation with the latest night vision gear during the 80's, the Chinese were lagging even more and the North Koreans lagged so hard it's not even clear that they had arrived technologically in the 60's (which featured night vision devices that had to emit near infrared light themselves such as this toy).
The whole night vision thing was terribly dangerous to North Korea, even if it had the newest toys itself in quantity. The light infantry infiltration techniques depended a lot on the concealment of darkness, and became much less credible due to the improved surveillance at night.
So North Korea changed its deterrence fundamentally. It stopped paying attention to impressing officers in-the-know (who were increasingly rare anyway) and turned towards impressing politicians, pundits and journalists.
This required different things than light infantry skills; something spectacular* was needed.
(1) North Korea turned towards long-range artillery in useless bunkers situated close to Seoul in order to threaten with shelling the city.
(2) North Korea turned towards the ballistic missiles that had scared people with no or superficial knowledge of military affairs so much during the Gulf War in '91.
(3) Finally, it turned towards the ultimate attention-grabbing device: A fission nuke.
They succeeded in impressing enough - and more importantly, the right people. Now they're being left alone, even supported with food deliveries. Deterrence mission accomplished.
Maybe - just maybe - the next time I fail to be impressed by North Korean (or for that matter Iranian) signals of "threat", readers of Defence and Freedom will remember why.
*: There was a 4th spectacular ingredient of the deterrence strategy: They declared a huge portion of their troops to be "special forces". Saddam attempted the same, but his bluff was called. Most North Korean "special forces" were and are apparently simply the continuation of their trained light infantry of summer '50. In other words: They're probably freed form being sent to rice harvest, or to work in mines and factories. They have definitively no waiver for the huge ballets known as military parades.