The “open” strategic autonomy discourse now serves altogether as a new narrative and overarching principle of EU energy policy. This article conceptualizes EU strategic energy autonomy (SEA) as the Union’s ability to choose autonomously its own path towards a decarbonized “energy mix”. Realizing EU SEA demands a more holistic energy policy to tackle external dependence on foreign suppliers of energy commodities, technologies, and raw materials critical to the green transition. In this context, joint external action is important; but coordinated internal action is even more so, as the nature and magnitude of external constraints also depend on internal choices among the Member States concerning transition pathways. The article focuses on the internal dimension of EU energy policy. The REPowerEU plan and related emergency measures adopted under Article 122 TFEU to guarantee solidarity in tackling the impending energy crisis only brought a partial answer and once again raised the question of the EU competence to act on energy security issues. It is argued that the shared competence and related limitations foreseen in the TFEU should not prevent the EU from implementing a long-term holistic policy to pursue a resilient decarbonization policy throughout the energy value chains. The EU may well become more relevant than in the past when it comes to the energy security of Member States. New regulatory tools may be needed to support the integrity of the cornerstone of EU energy policy to date – the internal energy market – in the pursuit of an “open” SEA. The potential contribution to safeguarding “open” SEA from EU foreign direct investment screening, the forthcoming carbon border adjustment mechanism, and the new EUforeign subsidy regulation are discussed in this context.