President Trump's "fire and fury" comment has solicited an even stronger verbal retaliation from North Korea. A few hours after the president issued his warning, North Korea reacted with a threat of a missile strike on the U.S. Pacific territory of Guam. And Trump has not backed down, wondering Thursday afternoon if his previous warning "wasn't tough enough."
To assess the real probability of war requires an accurate understanding of the U.S. capability and political will to launch a preemptive strike on North Korea. No one questions that U.S. has such technical capability. However, it is the political, military, economic, and diplomatic consequences of such an attack that makes it an undesired option.
The disastrous result of a preemptive strike on North Korea is well understood among policy-makers and military analysts. Conventional wisdom holds that first, without being provoked, the U.S. would not lightly resort to such an extreme option; and second, North Korea as a "rational actor" will not provoke the U.S., an act of suicide. However, what people are indeed concerned with is whether the president's verbal spat with Pyongyang could lead to North Korea's serious miscalculation of U.S. intention, and whether the U.S. will stumble into a nuclear war with North Korea inadvertently.
It's clear that the military option comes with significant risk. A U.S. preemptive strike, namely a targeted nuclear attack to take out North Korea's nuclear weapons, would invite all-out retaliation by North Korea against South Korea, Japan, and U.S. troops in the region. With the massive conventional artilleries deployed near the Korean Demilitarized Zone, North Korea would inflict major casualties on the South.
If the U.S. resorts to a preemptive strike on North Korea without consultation and agreement from Seoul, the costs to South Korea would have a critically damaging effect over the U.S.-South Korea alliance, even possibly lead to its dissolution. Considering President Moon Jae-in's interest in engagement with North Korea, it would be highly unlikely for South Korea to support a U.S. decision to launch a targeted nuclear attack on the North.
A U.S. preemptive strike on North Korea would also likely invite Chinese intervention. The Sino-North Korea Friendship, Cooperation, and Mutual Assistance Treaty commits China to North Korea's defense in the event of foreign aggression. Although the validity of the 56-year old treaty is constantly debated, few doubt that China would intervene to defend its perceived national interests in the Korean Peninsula, including the preservation of a North Korean state and the prevention of a South Korea-led unification. It would put U.S. and China directly on a collision course and could lead to another Korean War.
Clear signaling is necessary in dealing with North Korea and its leader, Kim Jong-un. Since no one can predict Kim's next move with full confidence, the U.S. should send clear signals and warnings on the dire consequences to deter any ill-contemplated provocation by North Korea. The need to deter requires the preparedness for a preemptive strike and clear messaging to Pyongyang. Nevertheless, there is always the danger that the effort to deter North Korean attack might be misinterpreted and lead to the precise situation that it sets out to prevent.
This is also exactly why we are seeing so much debate over the military options on North Korea. No one sees it as a desired option, yet no one can take the option off the table. I don't believe a preemptive strike, or a nuclear war with North Korea, is imminent. And I don't believe either the U.S. or North Korea are intentionally pushing for a war. Nevertheless, with loose rhetoric backed by powerful weapons, the danger exists.
Yun Sun is a senior associate with the East Asia program at the Stimson Center.