Nobody (the clinically insane excepted) thinks that a Second Korean War — or, technically, a renewal of hostilities from the first — would be anything but horrific. The Korean War ended in 1953 not with a peace treaty, but with an armistice, which means both sides are still technically at war with one another. That technical state of war has fortunately failed to flare up into actual high-intensity conflict for the past 60 years. Fortunate, because both sides have spent the past six decades digging in, fortifying, and coming up with new ways to kill each other quicker.
Say what you will about how nuts the North Koreans are, but there really aren’t many scenarios in which either side would willingly choose all-out war. Sure, it's possible the North could go postal one day — the regime realizes it's on the brink of implosion and chooses to commit suicide by war instead of being torn apart by the North Korean mob — but it's not a likely scenario.
Similarly, war could break out after tit-for-tat posturing — a common occurrence on the peninsula — gets out of hand and sparks a game of chicken in which neither side actually wants a war, but neither side feels it can afford to back down. In that scenario, one side or the other would eventually decide to go for broke before the enemy got the jump on them.
The North’s threats to turn Seoul, which is about the size of New York City, into a “sea of fire” might be infused with just a bit of hyperbole. But even if the regime couldn't obliterate Seoul as easily as they've claimed, they could certainly deliver a whole bunch of death and destruction literally minutes after an order from Kim Jong-un; Seoul is only about 30 miles from the North Korean border. Not to mention the ever present threat of WMDs and the network of infiltration tunnels the North is known to have dug under the DMZ and into the South.
The South has discovered at least four of these tunnels over the years, three of which were big enough to allow 30,000 troops through every hour — and experts estimate as many as 20 tunnels may exist. North Korea also maintains the world’s largest Special Forces contingent, numbering between 87,000 and 200,000 personnel. And so, (very) theoretically, less than half an hour after the start of a war, the South Korean countryside could be crawling with more than 100,000 DPRK Special Forces troops.
Of course, the advanced stealth fighters, bunker-penetrating munitions, drones, and host of other military technologies now employed by the South Korean and US militaries will be very much in their way.
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In 1994, the US was worried its confrontations with North Korea over nuclear weapons could escalate into a war. Senior military leaders told President Bill Clinton that he could expect 52,000 US and 490,000 South Korean dead and wounded in the first 90 days — not to mention “enormous” North Korean casualties. Other sources put the number of US casualties somewhere between 80,000 and 100,000. Granted, those estimates are now 20 years old, and these kinds of numeric guesses are wildly speculative hand waving to begin with. But the gist is that any kind of major war in Korea could create five to 10 times as many casualties in its first 90 days as the US has suffered in Iraq and Afghanistan in total, combined. Put another way, a renewed Korean War could produce roughly two to three times as many casualties in 90 days as the initial Korean War did in more than three years.
This is just one of many reasons why South Korea has been steadily pursuing means to cripple the North Korean WMD stockpile. An example: the decision to equip F-15K aircraft with advanced, long-range weapons to sever critical command and control links with the hope that such a strike would prevent the order to use WMD from ever reaching the field.
North Korea could be a flashpoint for a war between the US and China.
South Korea has also been developing its own ballistic missiles — some of which were tested earlier this year — to extend its ability to prevent the use of the North’s missiles and WMD. The new missiles were developed, in part, so that South Korea could reach out and hit the North's launch sites on the other side of the country, near the Chinese border.
Trying to dismantle the North Korean WMD program in the middle of fighting a war would be like trying to defang a cobra while wrestling with it. A perilous task, but probably still better than ignoring the fangs altogether.
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Even without a full-fledged war, South Korean and US troops may still find themselves marching over the border. There are a whole range of contingencies for this, most of which revolve around a sudden collapse of the North Korean government.
China is also aware that an imploding North Korea would be a nightmare, and has therefore authorized its Army to stabilize the situation. In a 2004 trial of a South Korean intelligence agent who was caught passing information to the North, information about Chinese plans came to light. It’s impossible to confirm or verify what an intelligence agent who turned against his country has to say about the secret plans of a third country. But according to his testimony, the Chinese military plan is codenamed “Chick” — as in the hatchling of a mother hen — and involves moving troops into North Korea until they halt on a line between Wonsan and Nampho, just south of Pyongyang and about 70 miles north of the DMZ.
In theory this would be terrific, because an imploding North Korea will need all the peacekeeping and stabilization it can get. In practice, it could be a flashpoint for a war between the US and China.
Imagine a collapsing North Korea in which some isolated units of the North Korean army, cut off from each other, opt to stand and fight invaders from the north and south. Meanwhile, other units stand aside. Some throw down their weapons. Still others choose to join either their Korean brethren or their Chinese allies. Also, there are loose WMDs and a terrible humanitarian crisis. Now add to this crisis the US (marching from the south) and Chinese (marching from the north) bearing down on each other at full speed. It may not end well.
The US is known to have at least two major operational plans for what to do if shit goes down in Korea. While the current iterations are classified, details about them have been dribbling out for years. The first is OPLAN 5027, titled “Major Theater War — West,” and is the current evolution in the ongoing preparation for a rematch of the Korean War. The plan involves the US and South Korea forces moving back to absorb the first blow from the North, then hitting advancing North Korean forces with long-range attacks while US and South Korea mobilize to roll the North Koreans all the way back to Pyongyang (and beyond, if need be). The other plan, OPLAN 5029, deals with other contingencies that would involve US and South Korean troops moving north — like the implosion of the regime. The details of this plan are less well known, but watchers have been predicting the imminent demise of North Korea for decades, so this plan might be the one that actually ends up seeing the light of day.
Either way, the US and South Korea are currently revisiting their plans for a large, heavily armed, unguided tourist visit to the DMZ and beyond. Which, all in all, is probably a good thing, since the South doesn’t appear to be committed to taking the concrete measures needed to pursue a peaceful reunification, if that's even still possible. The Korean War is dead — long live the Korean War.
Follow Ryan Faith on Twitter: @Operation_Ryan