First published here.

Resilience is a “new” term creeping into military directives, but what does it mean and how do we use it to guide decisions? In the previous resilience corner, we discussed how resilience should be differentiated from established notions of risk as the two concepts are fundamentally different. Resilience is more like a verb than a noun, and resilient military systems should be designed to handle any possible problem instead of only pre-defined threat scenarios. But how do we start approaching this problem of resilient design when we cannot define specific threats?

In a recent article published in the journal Risk Analysis, we answered this question by relying on military theories of surprise (Eisenberg et al. 2019). Surprise has always played an important role in military activities by influencing intelligence and operational decisions to generate a surprise attack and overtake an adversary or to avoid being surprised and overtaken. Historical examples of surprise attack on allied forces teach us the kinds of situations we should focus on for resilient design. Reflecting on the Yom Kippur War of 1973, when a combined Libyan and Egyptian attack took Israel by surprise and nearly overwhelmed Israeli forces, Zvi Lanir defined at least two kinds of surprise we should be resilient to (Lanir 1986): situational and fundamental surprise (see Table 1).

To help make sense of surprise for design, we distinguish surprise from normal events with an example from the lottery. Normal events are when you buy a lottery ticket and lose. Situational surprises are rare events like buying a lottery ticket and winning. Fundamental surprises are the unimaginable events like when you do not buy a lottery ticket and you still win.

Resilience asks us to design our military systems to handle all these events, especially the fundamental surprises that lie outside our current understanding. This means resilient design starts with a different question than normal design processes. Rather than asking the question, “what threats do we care about?” before approaching starting to design resilient systems, we should ask, “what plans, processes, and capabilities do we have in place to respond to situational and fundamental surprises?” Importantly, there should be a greater emphasis on learning from historical examples of military surprise prior to making any design decisions to improve resilience.


Eisenberg, Daniel. “Resilience Corner: Think of Resilience as a Verb, not a Noun.” (2019).

Eisenberg, Daniel, Thomas Seager, and David L. Alderson. “Rethinking Resilience Analytics.” Risk Analysis(2019).

Lanir, Zvi. “Fundamental surprise.” Eugene, OR: Decision Research(1986).