The last article that we are republishing as part of 70 Years of NATO Review was written by consistent and long-time NATO Review author, Michael Rühle, in April 2015. While that might not seem like very long ago, this piece is evidence of just how much has changed in the last eight-or-so years. In the 2000s and early 2010s, deterrence had become a dormant concept, all but cast aside at the end of the Cold War to make space for countering new challenges and enlarging the Alliance. In 2014, following Russia’s illegal annexation of Crimea, deterrence was pulled out and dusted off to take centre stage as one of NATO’s traditional core tasks and the backbone to Article 5. Russian aggression in Ukraine highlighted the necessity of ensuring that NATO’s deterrence and defence posture was and would remain credible and effective.