After decades of successful growth, economic unions have recently become the focus of heightened political controversy. We argue that this is partly due to the growth of trade between countries that are increasingly dissimilar. We develop a theoretical framework to study the effects on trade,...

Are country borders still an impediment to trade flows within Europe? Using a rich microlevel survey with 3 million annual shipments of goods by road across 269 European regions, we construct a matrix of bilateral trade flows for 12 industries from 2011 to 2017. We then use the causal inference...