Korean People's Army soldiers attend a mass celebration on Sept. 6 in Pyongyang for scientists involved in carrying out North Korea's largest nuclear blast to date. (Kim Won-Jin/AFP/Getty Images)
Bradley DeWees is a captain in the Air Force and a doctoral student in decision science and public policy at the Harvard Kennedy School. The views expressed here are his and do not necessarily reflect those of the U.S. government or any part thereof.

North Korea’s recent nuclear and missile developments — including what it claimed to be a test of a hydrogen bomb, and a missile test that led the Japanese government to advise its citizens to take cover — have brought Pyongyang and Washington to a level of tension not seen since the Korean War. Options for dealing with the crisis include containment of a nuclear North Korea as well as military action that would set back its nuclear progress. Experts tend to agree that none of the options are good.

The United States does, however, have better and worse ways to decide on a North Korea strategy. Framing the decision in the right way — asking not just “Why should we do this?” but “At what price do other options become more attractive?” — could make the difference between war and peace.

Selecting from options such as containment or military action can take two forms — what decision scientists call “choice” or “matching.” “Choice” requires a decision-maker to separate options from one another, while “matching” requires the decision-maker to equate options with one other.

Choice would lead a decision-maker to ask why containment is better than military action (or vice versa). This “why?” question triggers a search for good reasons to adopt or reject an option. Matching, by contrast, would lead a decision-maker to ask how much (or how little) military action would have to cost before it was as desirable as containment. This “how much?” question triggers a quantification of the dimensions common to each option.

The two processes can lead to different outcomes because choice — and the concomitant search for “good reasons” — can bias a decision-maker in several ways.

Choice pushes people toward the option scoring highest on the most important criterion, even if that option leads to a worse overall outcome. The criteria at stake in this decision include lives, money, living under the risk of a nuclear North Korea and maintaining the credibility of public threats. In the latter category would be statements such as one President Trump made on Aug. 8: “North Korea best not make any more threats to the United States. They will be met with fire and fury like the world has never seen.” If maintaining the credibility of threats like this is the most important criterion to the administration, choice would favor a military option. Choice also would predispose a military option if preventing a nuclear North Korea is the most important criterion to the administration, as recent statements by national security adviser H.R. McMaster imply: North Korea having “nuclear weapons that can threaten the United States” would be “intolerable from the president’s perspective.” In both cases, acting on one’s most important criterion constitutes a good reason.

Matching could lead to a different decision even if the relative importance of each criterion remained unchanged. Using matching, the task would be to say how much, in lives and money, one values avoiding the risk of a nuclear North Korea or maintaining the credibility of public threats. What containment lacks on these criteria it could make up for in saving lives and money. Matching wouldn’t predestine the outcome — preventing a nuclear North Korea or maintaining credibility could still be important enough to justify military action, but a decision-maker would have to directly confront the cost of what Defense Secretary Jim Mattis has said would be the “worst kind of fighting in most people’s lifetimes.”

Choice based on reasons factors a decision-maker’s audience into the decision. What counts as a good reason depends on what a decision-maker’s audience thinks is a good reason. This is important in the context of a North Korea strategy, because the decision could change based on who a decision-maker has in mind when deciding. Is a military adviser thinking of troops? A political leader thinking of supporters? Of history? What counts as a good reason for one group may not necessarily be good for another. Matching, on the other hand, is more stable across audiences — the audience is unlikely to affect the numbers underlying the decision.

Choice based on reasons also allows a bigger role for emotions. In the context of national security decisions, this is perhaps the most important difference. When members of a staff, military or country feel anger, fear or a desire not to appear weak, using those emotions as reasons for acting can be simple and compelling. As Ambassador Nikki Haley argued this past week in trying to get the U.N. Security Council to act: “North Korea basically has slapped everyone in the face in the international community that has asked them to stop.” Such emotions could push us toward a military option. Matching, on the other hand, would limit the effect emotions can have on a decision — stating how many lives and dollars one is angry would be difficult, and even more difficult to defend to others.

I have no inside knowledge of the administration’s decision process, but it probably is relying on choice. I say this for two reasons. First, choice is more natural for people. In our own lives, we’re more likely to reach for good reasons rather than expend extra mental effort on quantification. Second, the administration’s most recent national security decision — selecting a strategy for Afghanistan — seemed to rely on choice. As the defense secretary said just before the Afghanistan decision was made: “We’re sharpening each one of the options so you can see the pluses and minuses of each one. . . . Now just make the decision.” Reporting of that decision process described a menu of options, and the president chose the one he deemed most desirable.

Importantly, even if the pluses and minuses of each option are quantified, quantification alone does not imply matching. Matching would require senior policymakers themselves to step through the quantification to decide which option is most desirable. It’s the act of quantification — of asking oneself “how much?” rather than “why?” — that insulates a decision-maker from bias.

Matching and the quantification associated with it are unnatural and even morally uncomfortable when the stakes include human lives, but when it comes to a situation as dangerous as the standoff with North Korea, it’s important to force an unnatural decision process. To be sure, a decision process does not make the decision easier — it cannot change the fact that risk and benefit are positively correlated. What a good process can do, though, is ensure the United States confronts the standoff consistently and with a complete understanding of what is in its best interest. In a turbulent world, consistency and completeness can be achievements of their own.

Twitter: @b_dewees

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