Whatever the political realities may seem to dictate after a North Korean nuclear test, an overt military strike — even one limited to cruise missiles — is not in the cards. The consequences of even the most restrained attack could be devastating.

Analysis

The reported detonation of a nuclear device by North Korea on Oct. 9 raises the question of potential military action against North Korea. The rationale for such a strike would be simple. North Korea, given its rhetoric, cannot be allowed to have nuclear weapons. Therefore, an attack to deny them the facilities with which to convert their device into a weapon and deploy it is essential. If such an attack were to take place, it is assumed, the United States would play the dominant or even sole role.

This scenario assumes that North Korea is as aggressive as its rhetoric.

But what about North Korea’s well-armed neighbors — Russia, China, South Korea, Japan? Would they not be willing to assume the major burden of an attack against North Korea? Is the United States really willing to go it alone, even while engaged in combat in Iraq and Afghanistan?

Leaving these obvious political questions aside for the moment, let’s reverse the issue by posing it in military terms: What would a U.S. strike against North Korea look like?

The USS Kitty Hawk is currently sitting in port at Yokosuka Naval Base, Japan. The USS Enterprise is operating in the Arabian Sea, while the Nimitz and the Stennis are conducting exercises off the coast of California. All are an ocean away, and none is less than a week’s transit from the region. Nevertheless, naval cruise missiles are readily available, as are long-range strikes by B-2A Spirit stealth bombers and B-52H Stratofortresses and B-1B Lancers currently supporting NATO operations in Afghanistan out of Diego Garcia. A more robust strike package would take longer to deploy.

When U.S. military planners have nightmares, they have nightmares about war with North Korea. Even the idea of limited strikes against the isolated nation is fraught with potential escalations. The problem is the mission. A limited attack against nuclear facilities might destabilize North Korea or lead North Korea to the conclusion that the United States would intend regime change.

Regime preservation is the entire point of its nuclear capability. Therefore, it is quite conceivable that Kim Jong-Il and his advisors — or other factions –might construe even the most limited military strikes against targets directly related to missile development or a nuclear program as an act threatening the regime, and therefore one that necessitates a fierce response. Regime survival could very easily entail a full, unlimited reprisal by the Korean People’s Army (KPA) to any military strike whatsoever on North Korean soil.

North Korea has cultivated a reputation for unpredictability. Although it has been fairly conservative in its actions compared to its rhetoric, the fact is that no one can predict North Korea’s response to strikes against its nuclear facilities. And with Seoul at risk — a city of 20 million people — the ability to take risks is limited.

The United States must assume, for the sake of planning, that U.S. airstrikes would be followed by massed artillery fire on Seoul. Now, massed artillery is itself not immune to countermeasures. But North Korea’s artillery lies deep inside caves and fortifications all along the western section of the demilitarized zone (DMZ). An air campaign against these guns would take a long time, during which enormous damage would be done to Seoul and the South Korean economy — perhaps on the order of several hundred thousand high-explosive rounds per hour. Even using tactical nuclear weapons against this artillery would pose serious threats to Seoul. The radiation from even low-yield weapons could force the evacuation of the city.

The option of moving north into the North Korean defensive belt is an option, but an enormously costly one. North Korea has a huge army and, on the defensive, it can be formidable. Fifty years of concerted military fortification would make Hezbollah’s preparations in southern Lebanon look like child’s play. Moving U.S. and South Korean armor into this defensive belt could break it, but only with substantial casualties and without the certainty of success. A massive stalemate along the DMZ, if it developed, would work in favor of the larger, defensive force.

Moreover, the North Koreans would have the option of moving south. Now, in U.S. thinking, this is the ideal scenario. The North Korean force on the move, outside of its fortifications, would be vulnerable to U.S. and South Korean airstrikes and superior ground maneuver and fire capabilities. In most war games, the defeat of North Korea requires the KPA to move south, exposing itself to counterstrikes.

However, the same war-gaming has also supposed at least 30 days for the activation and mobilization of U.S. forces for a counterattack. U.S. and South Korean forces would maintain an elastic defense against the North; as in the first war, forces would be rushed into the region, stabilizing the front, and then a counterattack would develop, breaking the North Korean army and allowing a move north.

There are three problems with this strategy. The first is that the elastic strategy would inevitably lead to the fall of Seoul and, if the 1950 model were a guide, a much deeper withdrawal along the Korean Peninsula. Second, the ability of the U.S. Army to deploy substantial forces to Korea within a 30-day window is highly dubious. Desert Storm and Iraqi Freedom both required much longer periods of time.

It comes down to this: If the United States strikes at North Korea’s nuclear capabilities, it does so placing a bet. And that bet is that North Korea will not respond. That might be true, but if it is not true, it poses a battlefield problem to which neither South Korea nor the United States will be able to respond. In one scenario, the North Koreans bombard Seoul and the United States makes a doomed attempt at shutting down the massive artillery barrage. By the time the guns are silenced — even in the best-case scenarios — Seoul will be a mess. In another scenario, the North Korean army executes an offensive of even minimal competence, which costs South Korea its capital and industrial heartland. The third is a guerrilla onslaught from the elite of the North Korean Army, deployed by mini-subs and tunnels under the DMZ. The guerrillas pour into the south and wreak havoc on U.S. military installations.

That is how a U.S. strike — and its outcome — might look. Now, what about the Chinese and Russians? They are, of course, not likely to support such a U.S. attack (and could even supply North Korea in an extended war). Add in the fact that South Korea would not be willing to risk destroying Seoul and you arrive at a situation where even a U.S. nuclear strike against nuclear and non-nuclear targets would pose an unacceptable threat to South Korea.

There are two advantages the United States has. The first is time. There is a huge difference between a nuclear device and a deployable nuclear weapon. The latter has to be shaped into a small, rugged package able to be launched on a missile or dropped from a plane. Causing atomic fission is not the same as having a weapon.

The second advantage is distance. The United States is safe and far away from North Korea. Four other powers — Russia, China, South Korea and Japan — have much more to fear from North Korea than the United States does. The United States will always act unilaterally if it feels that it has no other way to protect its national interest. As it is, however, U.S. national interest is not at stake.

South Korea faces nothing less than national destruction in an all-out war. South Korea knows this and it will vigorously oppose any overt military action. Nor does China profit from a destabilized North Korea and a heavy-handed U.S. military move in its backyard. Nevertheless, if North Korea is a threat, it is first a threat to its immediate neighbors, one or more of whom can deal with North Korea.

In the end, North Korea wants regime survival. In the end, allowing the North Koran regime to survive is something that has been acceptable for over half a century. When you play out the options, the acquisition of a nuclear device — especially one neither robust nor deployable — does not, by itself, compel the United States to act, nor does it give the United States a militarily satisfactory option. The most important issue is the transfer of North Korean nuclear technology to other countries and groups. That is something the six-party talk participants have an equal interest in and might have the leverage to prevent.