This study examines the concept of European strategic autonomy, which has been spreading since Brexit and the emergence of the Trump administration, and forecasts how this concept will affect the European security cooperation. The French Defense White Paper of 1994 first introduced the concept of strategic autonomy as an autonomy of military evaluation, planning, and decision-making to achieve French independence and freedom of political action. The strategic autonomy at the EU-level emerged since 2010 and began to receive attentions to support a series of programs to effectively achieve the goals of the Common Security and Defense Policy (CSDP). Recently, France has emphasized strategic autonomy in the context of bilateral cooperation with Germany for the EU’s increased operational capabilities to cope with the conflict with the U.S. over NATO. This study argues that the concept of European strategic autonomy is based on multi-layered discourses depending on the issue and context. Discussions on European strategic autonomy are still ongoing, and its nature will be redefined in accordance with changes in the international security environment and in solidarity of the trans-Atlantic alliance.