George Friedman of Stratfor singles out South Korea as the wild card in the dangerous North Korea game:
[The North Koreans] seemed to be acting as if they had no fear of a war breaking out. It wasn’t just the many photos of Kim Jong Un smiling that gave this impression. It was that the North Koreans moved forward with their program regardless of American and possible Chinese pressure.
Another Player Enters the Game
A couple of weeks ago, the reason for their confidence became evident. First, US President Donald Trump tweeted a message to the South Koreans accusing them of appeasement. In response, the South Koreans released a statement saying South Korea’s top interest was to ensure that it would never again experience the devastation it endured during the Korean War. From South Korea’s perspective, artillery fire exchanges that might hit Seoul had to be avoided. Given the choice between a major war to end the North’s nuclear program and accepting a North Korea armed with nuclear weapons, South Korea would choose the latter.
With that policy made public, and Trump’s criticism of it on the table, the entire game changed its form. The situation had been viewed as a two-player game, with North Korea rushing to build a deterrent, and the US looking for the right moment to attack. But it was actually a three-player game, in which the major dispute was between South Korea and the United States.
The US could have attacked the North without South Korea’s agreement, but it would have been substantially more difficult. The US has a large number of fighter jets and about 40,000 troops based in the South. South Korean airspace would be needed as well. If Seoul refused to cooperate, the US would be facing two hostile powers, and would possibly push the North and the South together. Washington would be blamed for the inevitable casualties in Seoul. The risk of failure would pyramid.
Comment on this from an author and military vet:
Short of such an all-out nuclear attack, any US military intervention in North Korea must inevitably involve South Korea. If South Korea is not willing to permit its territory, or its airspace, or its waters, to be used for that purpose, the USA is effectively stymied.
I see only one way to break the logjam, and force the issue. That would be for the USA to announce that, in view of North Korea’s aggressive actions and stated intentions to become a nuclear power, it is willing to sell nuclear weapons to Japan and South Korea. Note that I said “sell” – in other words, not station US nuclear weapons in those countries under US control, but give each country its own nuclear warheads and delivery systems, under its own sovereign control. China would instantly have kittens – a nuclear-armed Japan must be close to its worst nightmare, and a nuclear South Korea wouldn’t be far behind that. If anything could force China to rein in the North Korean regime, that might do it.
It’s worth pointing out that a growing number of South Koreans want nukes of their own:
Throughout much of the Cold War, the United States had stationed nuclear-armed weapons in South Korea. Then, in 1991, President George H.W. Bush withdrew all tactical nuclear weapons deployed abroad, and Moscow reciprocated.
The debate over redeploying those weapons is sharply dividing South Korean politics. […]
Still, 60 percent of South Koreans in theory support nuclear weapons for their country, according to Gallup Korea. A poll by YTN, a cable news channel, in August found that 68 percent of respondents supported redeploying tactical nuclear weapons to South Korea.
After South Korea’s defense minister said earlier this month that it was worth reviewing a redeployment of tactical nuclear weapons, other administration officials have distanced the Blue House — South Korea’s executive mansion — from the proposal. Foreign Minister Kang Kyung-wha said this week that South Korea is not considering the option and has not discussed it with Washington, but she acknowledged that public opinion is shifting toward supporting the option. […]
“The mainstream view is now changing in South Korea,” Kim said. “Even within the governing party, we are now hearing some of these voices who are supporting redeployment or South Korea going nuclear by herself, particularly after North Korea’s sixth nuclear test.”
Defense chiefs James Mattis and Song Young-Moo
As for Japan going nuclear:
Then there is the anomaly of Japan’s nuclear status. Defense analysis privately agree that Japan, like Israel, is an undeclared member of the nuclear weapons club. The point was made explicitly in an article by Nick Rufford in the London Sunday Times in 1994. The British Defense Ministry, Rufford reported, had informed Prime Minister John Major that “Japan has acquired all the parts necessary for a nuclear weapon and may even have built a bomb which required only enriched uranium for completion.” Moreover, Japan has long held enormous stockpiles of plutonium for its nuclear power program, and its H-2 rocket, which has launched two satellites into orbit, is regarded as capable of delivering a nuclear strike. Writing in the Washington Quarterly, Marc Dean Millot commented: “This is the stuff of virtual nuclear power. Only a political decision is needed to make it real.”