The run-up to the 2016 NATO Summit in Warsaw and the coming U.S. presidential election have brought NATO’s future into sharp focus on both sides of the Atlantic. Detractors claim the alliance is a Cold War relic, and that it does not and cannot rise to meet the multi-dimensional security challenges of the 21st century. Nevertheless, NATO’s 28 member states still affirm its strategic utility and invest in its capabilities. In the coming months and years, NATO must continue to modernize and adapt in response to rising threats. This is especially the case with cyber defense, which will play an increasingly pivotal role in the alliance’s postures and plans. It is time to start moving toward NATO deterrence for the cyber domain.