Questions surrounding the logic of nuclear deterrence (as well as the subtleties of signaling and risks of inadvertent escalation) are very relevant right now. In fact, the current crisis reveals the need to invest (and to keep investing) in knowledge and expertise in this field. Nuclear threats have not been on our mind for a few years but all of a sudden, it is at the forefront again. The nuclear threat is back and we have to work with that. Regarding deterrence, in my personal opinion, NATO and the United States have been quite understanding of what deterrence means. We have been pretty clear in signaling to Russia that we are closely following the steps being taken and that a nuclear war and/or attack would be totally unacceptable. At the same time, we have been reinforcing our defense and our deterrence posture. It is about striking the right balance between words and deeds. The United State has done a good job of not escalating the situation further. For example, they decided to postpone their test of Minuteman III, which was a really smart decision. However, what this crisis has made clear is that deterrence exists not only in relation to having nuclear weapons, but also in relation the credibility of using them—this is a balance that is really important and that has been going well so far. Though, nowadays, it is very difficult to “predict people who are unpredictable” and this is the current challenge we face.