An unprecedented amount of nuclear-related signals originating from the Kremlin, including statements, bomber flights, and exercises, demonstrates that during the Ukraine crisis Russia has deliberately sent nuclear messages to NATO. Russia’s nuclear muscle-flexing has been an integral part of Moscow’s approach to conflict, backing up the credibility and effectiveness of its hybrid warfare campaign.NATO has responded in a very restrained manner and rightly avoided engaging in tit-for-tat nuclear messaging with Russia. At the same time, however, the Ukraine crisis has exposed NATO’s communication gaps and corresponding challenges to the effectiveness of NATO’s nuclear deterrence and assurance. To adapt to the new nuclear landscape in Europe, the NATO Allies should consider rebalancing their thinking towards nuclear deterrence, a re-examination of their nuclear crisis-management tools and exercises, refreshing declaratory policy and re-designing their nuclear communication strategy.