We use the 2018-2019 U.S. trade war to examine how supply chains adjustments to a tariff cost shock affect imports and exports. Using confidential firm-trade linked data, we show that the decline in imports of tariffed goods was driven by discontinuations of U.S. buyer-foreign supplier...

Empirical studies have found that enhanced foreign competition can encourage or discourage innovation. To address this relationship, I examine a market structure in which a small number of large multi-product oligopolists compete with a large number of small single-product firms in the same...

The U.S. opioid crisis is now driven by fentanyl, a powerful synthetic opioid that currently accounts for 90% of all opioid deaths. Fentanyl is smuggled from abroad, with little evidence on how this happens. We show that a substantial amount of fentanyl smuggling occurs via legal trade flows,...

Global supply chains have come under unprecedented stress as a result of US-China trade tensions, the Covid-19 pandemic, and geopolitical shocks. We document shifts in the pattern of US participation in global value chains over the last four decades, in terms of partner countries, products, and...

How does the interplay of geography and political-economic forces affect the shape of nations? This paper presents a quantitative framework for characterizing the equilibrium evolution of national boundaries in a world with a rich geography. The framework delivers simple equilibrium conditions...

This paper studies the implications of household heterogeneity for trade. I develop a model where household heterogeneity is induced via incomplete markets and results in heterogeneous price elasticities. Conditional on exposure to trade, heterogeneous price elasticities imply that different...

With average temperature ranging from -20°C at the North Pole to 30°C at the Equator and with global warming expected to reach 1.4°C to 4.5°C by the year 2100, it is clear that climate change will have vastly different effects across the globe. Given the abundance of land in northern...

We study optimal dynamic trade policies in an Eaton-Kortum model with technology diffusion through trade. The process of innovation and diffusion is one in which new ideas are combined with insights from others. Trade thus affects technology by determining the distribution from which producers...

This paper characterizes the allocations that emerge in general equilibrium economies populated by households with preferences of the additive random utility type that make discrete consumption, employment or spatial decisions. We start with a complete markets economy where households can trade...

During the recovery from the COVID-19 pandemic, international shipping and logistics capacity was strained, limiting the quantity of imports. We investigate the impact of an import constraint on inflation, following an increase in domestic demand. Whether the binding import constraint raises...