In a decree on the "policy of nuclear forces" adopted by the Supreme People's Assembly in September last year, North Korea stated that it could use nuclear weapons in the following cases:
1. It is determined that a nuclear or other weapons of mass destruction attack on the Democratic People's Republic of Korea has been carried out or is imminent.
2. It is determined that a nuclear or non-nuclear strike by hostile forces against the State leadership and the National Nuclear Force Command Organization has been carried out or is imminent
3. If it is determined that a deadly military attack on important strategic objects of the State has been carried out or is imminent;
4. When the operational necessity to prevent the escalation and prolongation of the war and to seize the initiative of the war is inevitably raised in case of emergency
. 5. In the event of a catastrophic crisis in the existence of other countries and the life safety of the people, creating an unavoidable situation in which we have no choice but to respond with nuclear weapons,
<Regarding the Nuclear Force Policy of the Democratic People's Republic of Korea, September 2022, 9>
The circumstances under which North Korea has stated that it will use nuclear weapons, such as when an attack is deemed imminent, when operational necessity arises, or when unavoidable circumstances arise, are quite arbitrary. Whether it is a nuclear attack or a non-nuclear attack, North Korea has made the possibility of nuclear preemption explicit by saying that it will use nuclear weapons whenever it chooses to use them.
North Korea's policy is nothing less than a declaration that "now that it is a nuclear state, no one should think of confronting North Korea." With confidence in the possession of nuclear weapons, they are bragging to their neighbors. Hinting that North Korea could use nuclear weapons if South Korea responds to North Korea's military provocations, North Korea intends to take the military initiative on the Korean peninsula.
North Korea's Offensive Nuclear Threat and the 'Washington Declaration'
The "Washington Declaration," adopted at the U.S.-ROK summit last month, is a response to North Korea's boasting of strength. As North Korea's nuclear threat intensified, it sought to counter North Korea's nuclear threat by demonstrating the United States' determination to deter expansion.
US President Biden himself referred to "the end of the North Korean regime in the event of a nuclear attack," once again summarizing the United States' willingness to retaliate against nuclear weapons.
What is important to note here is the correlation between North Korea's strength and the ROK-US response. As North Korea developed various types of nuclear weapons and escalated its nuclear threat, the United States and South Korea responded by increasing the level of extended deterrence.
The establishment of the NCG (Nuclear Consultative Group) provided a channel for South Korea's voice to be reflected in the military response to North Korea's nuclear crisis and announced that strategic nuclear submarines would come to South Korea. North Korea may have thought it could bring about military initiative on the Korean Peninsula through its aggressive use of nuclear weapons, but this only increased the level of the ROK-US response.
As there are effects and reactions in all situations, an escalation in North Korea's threat level will lead to an increase in the level of ROK-US response, not a unilateral change in the military situation on the Korean peninsula as North Korea wants.
Did North Korea secure the right to self-defense through nuclear development?
North Korea says it developed nuclear weapons in self-defense to counter threats from the United States. The United States, which has the world's strongest military and nuclear weapons, developed nuclear weapons to ensure the security of the North Korean regime.
If North Korea's nuclear development is in self-defense, as they claim, then North Korea's goal has now been achieved. Under the current circumstances, it is difficult for either the United States or South Korea to preemptively strike North Korea.
While North Korea's deterrence against the United States is still incomplete, with no confirmation of the technology for ICBM warheads to re-enter the atmosphere, North Korea has paved the way for a U.S. attack by threatening South Korea and Japan.
Given North Korea's short-range missile capability and the possibility of deploying tactical nuclear weapons, it is difficult for South Korea and Japan to start a war in advance unless they determine that North Korea cannot strike first or North Korea preemptively strike.
Considering the enormous damage that would occur from the fall of even one or two North Korean nuclear missiles, winning the war would not mean much.
Therefore, South Korea and Japan have no choice but to decisively prevent a U.S. attack on North Korea when the United States tries to preemptively attack North Korea. The United States cannot preemptively launch war with North Korea in the face of opposition from South Korea and Japan, two of Northeast Asia's major allies.
Securing deterrence even before nuclear development
In fact, North Korea had some deterrence against the United States even before it developed nuclear weapons. This is because South Korea did not want war on the Korean peninsula, regardless of whether the war was won or lost. In the event of war on the Korean Peninsula, victory for the U.S.-ROK coalition is self-evident, but damage to South Korea from an attack by North Korea's conventional forces is inevitable. Few South Koreans will believe that reunification should be achieved through war, even at the expense of such damage.
The 1994 war crisis exemplifies this. During the first North Korean nuclear crisis, U.S. President Clinton was about to carry out an airstrike on the Yongbyon nuclear facility. However, then-President Kim Young-sam took a position of opposition to the U.S. war.
The crisis was resolved through former U.S. President Carter's visit to North Korea before the war began, but even if the nuclear crisis had deepened, the United States would not have been able to launch an attack on North Korea in the face of the South Korean president's concerted opposition.
Since President Kim Young-sam opposed war because he was concerned about the enormous damage it would cause, North Korea was demonstrating its deterrent to war with conventional forces that could cause enormous damage to South Korea.
The crisis in the North Korean system does not come from the threat posed by the United States
As North Korea's nuclear weapons development has increased, it now has sufficient deterrence for war. In the event of a war, the ROK-U.S. coalition would win, but there is no possibility that South Korea and the United States will preemptively go to war at the risk of massive damage from a nuclear war.
(The rest of the story is from the soup)