The Nork artillery model has been exported to the Hezbollah in Lebanon. If this could be held off for a year, which I doubt, then the Israelis could sell several billion dollars worth of Iron Dome systems to the RoKs.
The RoKs should first up the ante by staging a massive civil defense exercise and evacuating the North suburbs and select districts of Seoul. If the balloon goes up they would have to anyway and it needs to be planned and tested. If the NorKs react by upping the ante, which I find unlikely but their apologists will have vapors predicting disaster from a provocative defensive response, then it will be better to have begun the evacuation earlier.
Legally there is a state of war and the Cease Fire, not even a real Armistice, is void for two reasons;
1. Even the wiki says, "North Korea unilaterally withdrew from the armistice on May 27, 2009, thus returning to a de jure state of war"
2. the terms of the agreement, seen here at Wikisource, have been violated point by point.
Given that legal condition there is no reason that the UN Command, that is the Americans, could not adopt a 3 step strategy to bring North Korea back into compliance with the agreement and other Security Council declarations;
1. evacuation of civilians within 40 km of the DMZ,
2. imposition of a blockade on the seas and airspace of North Korea,
3. destruction of the artillery sites and missile launch and WMD storage facilities.
None of this would require referral back to the UN Security Council for further deliberation. Legally we have the authority to go now. Step one is a purely defensive measure. Step 2 is legally an Act of War but as noted above the State of War already exists. Under this Step I would include the interception of aircraft over international waters and the destruction of naval assets. Step 3 is as I discuss below best done preemptively rather than in response to a Korean attack. If the Kim regime wishes to back down it can do so at any time, even after the destruction of its military assets. If it fails to do so then the last step would be the elimination of all regime officials. It would help to get China to see their interest in forestalling the violent end of their Pyongyang client. One way to do that would be to assure them that any resultant refugee flow would be as likely to be headed into their territory as South.
In terms of a time table I would think that Step 1 should take a week, there is a limit to how long the evacuation can be maintained before either relaxing it or moving on to Step 2. The second phase should last for two to three weeks. If the NorKs refuse all efforts to get them to restore the Cease Fire and abandon their threats to employ WMD then a coordinated campaign to destroy the tube and missile sites and WMD facilities should begin. At that point secrecy will not be our objective. Indeed we will want it to be absolutely clear to the Chinese and Russians what we will be doing.
My expectation is that if a war breaks out the NorK military will shatter. By the 1980s the same would have happened to Soviets on the Fulda Gap if some idiot had tried to push through to the Rhine. That does not mean that the threat was not real or had been exaggerated. It was very real and in the early 1950s Europe was very vulnerable. In the case of Europe as in the case of Korea there was a real possibility of massive civilian casualties during hostilities. In the case of Korea if the DPRK is given the initiative they could kill 250,000 or more civilians within the first 30 minutes. After 2 to 6 hours I would expect their ability to operate as an effective threat to be degraded. Four years from now after the impact of Obama's demilitarization of the United States is realized that ability to respond will be far less than it still is. We are actually more able to respond with conventional forces now than we were 40+ years ago. When the NorKs attacked the USS Pueblo it turned out that the only aircraft on strip alert were carrying nuclear payloads.
The ridiculous text of Nato's official response, not even delivered over the name of the Secretary General.
Classification: NATO UNCLASSIFIED
NATO Press release (2010)068 (Corr)
Statement by the NATO Spokeman on the sinking of South Korean Cheonan
NATO strongly condemns the North Korean actions which resulted in the sinking of the Cheonan, established in the findings of the multinational investigation. The Alliance expresses its sympathy over the loss of the 46 South Korean sailors and condemns the act of aggression that led to their deaths. The sinking of the Cheonan by North Korea constitutes a clear breach of international law and poses a serious threat to the region.
The North Atlantic Council has in the past strongly urged North Korea to refrain from actions which could contribute to raising tensions. Once again, NATO calls upon Pyongyang to fulfil its international obligations.
End of mail