This book blends analysis of Eastern European security needs, foreign threats, domestic political events, and public opinion, in theoretical ways to understand how they lead to future defense postures and commitments for each country in the region. How has NATO and EU membership improved their overall regional defense protection, and what ingredients are still missing for them on an individual state basis? Separate chapters treat clusters of states that make up the various regions of Eastern Europe. For example, the three threatened Baltic states in the north will receive careful analysis. Second, the complex array of states in the Balkan area of Southeastern Europe merit examination, for their security conditions have been quite varied and diverse. For some, NATO and EU membership has become a reality, and for others that possibility does not yet exist. Third, three of the four geographically central states were the ones that first gained full membership in NATO at the earliest possible moment in 1999. At present, Poland in the north has perceived clear threats from Russia since 2014, while the three other East-Central European states possess greater sense of security.