This could turn into a horrific situation. This article actually concerns a preemptive strike on North Korea's nuclear facilities. Now this current issue is slightly different. But, I suspect the consequences are pretty much the same.
but lets not underestimate what could or would likely follow:
Military Options for Dealing with North Korea's Nuclear Program
Phillip C. Saunders<1>
link:
http://cns.miis.edu/research/korea/dprkmil.htm"The biggest military concern in striking North Korean nuclear facilities is the threat of North Korean counter-attacks. Seoul, the South Korean capitol, lies within range of North Korean long-range artillery. Five hundred 170mm Koksan guns and 200 multiple-launch rocket systems could hit Seoul with artillery shells and chemical weapons, causing panic and massive civilian casualties. North Korea has between 500 and 600 Scud missiles that could strike targets throughout South Korea with conventional warheads or chemical weapons. North Korea could hit Japan with its 100 No-dong missiles.<7> Seventy percent of North Korean army ground units are located within 100 miles of the demilitarized zone separating North and South Korea, positioned to undertake offensive ground operations. These units could fire up to 500,000 artillery rounds per hour against South Korean defenses for several hours.<8> Finally, if North Korea does have one or two deliverable nuclear weapons, nuclear retaliation (or nuclear threats) would also be available to North Korea leaders.
Even if U.S. strikes on North Korea nuclear facilities are successful, North Korea would still have the capability to inflict massive damage against South Korea and the 37,000 U.S. troops based there. Retaliation might be gradual, or North Korea might resort to large-scale strikes quickly. Efforts to invade the South are less likely, but cannot be ruled out entirely (especially if U.S. military forces are preoccupied in the Persian Gulf). The decision about how to respond would be up to North Korean leaders, who would have a range of military options and the ability to escalate the conflict over time. Although the United States would likely win an all-out war, the damage to South Korea would be tremendous and U.S. forces would sustain large casualties. One U.S. military estimate suggested that U.S. and South Korean military forces might suffer 300,000-500,000 casualties within the first 90 days of fighting, in addition to hundreds of thousands of civilian casualties.<9>
Given these possible military responses, attacks against North Korean nuclear facilities would need to be accompanied by measures to prevent or limit retaliation, such as efforts to degrade North Korean military capabilities, defend against counter-attacks, and deter military responses.
Because North Korea has a wide range of military means (including artillery, missiles, and ground-force operations) that can inflict significant damage on the South, pre-emptive strikes could not destroy all of North Korea's weapons before they could be used. Pre-emptive strikes against North Korean artillery and missiles would require South Korean cooperation and the deployment of additional U.S. aircraft, reconnaissance assets, and artillery. Counter-battery artillery fire and air strikes could be used to target North Korea artillery, but would be unable to prevent North Korea from doing considerable damage to Seoul. The number and mobility of North Korea artillery pieces and ballistic missile forces make them particularly tough targets. Many North Korean artillery pieces are protected in caves and would be difficult to destroy; North Korean missiles are mounted on mobile launchers that are hard to locate and strike. As mentioned previously, any North Korean nuclear weapons would likely be hidden in hardened underground facilities. Because pre-emptive strikes against North Korean artillery and missiles would require striking targets throughout the country, they would quickly escalate the conflict into a wider war. For this reason, pre-emptive strikes would be unlikely to accompany surgical strikes against North Korean nuclear facilities, but would be held in reserve in case North Korea began to retaliate with missile and artillery attacks."
full article:
http://cns.miis.edu/research/korea/dprkmil.htm