What happens when a region accustomed to violent shifts in borders is subjected to a new, peaceful partitioning? Has the European Union spent the last decade creating a new Iron Curtain at its fringes? "Building Fortress Europe: The Polish-Ukrainian Frontier" examines these questions from the perspective of the EU's new eastern external boundary. Since the Schengen Agreement in 1985, European states have worked together to create a territory free of internal borders and with heavily policed external boundaries. In 2004 those boundaries shifted east as the EU expanded to include eight...