Many studies have found that international borders represent large barriers to trade. But how do international borders compare to domestic border barriers? We investigate international and domestic border barriers in a unified framework. We consider a data set of exports from individual US...

A key distinction which has emerged from heterogeneous firm models of international trade is that of exporting at the intensive and extensive margins. Empirically however, the two are often conflated, leading to biased estimates of the impact of falling trade costs. This paper exploits detailed...