Europe today is a continent of borders. The second-smallest continent in the world has more than 50 distinct, sovereign nation-states. Many of these are part of the European Union. At the core of the EU project is an effort to reduce the power and significance of these borders without actually abolishing them — in theory, an achievable goal. But history is not kind to theoretical solutions.
Today, Europe faces three converging crises that are ultimately about national borders, what they mean and who controls them. These crises appear distinct: Immigration from the Islamic world, the Greek economic predicament, and the conflict in Ukraine would seem to have little to do with each other. But in fact they all derive, in different ways, from the question of what borders mean.