We develop a dynamic extension of Dornbusch et al. (1977) with "rustiness": the home country has relatively higher unit costs tomorrow for goods it is not producing today. We solve for optimal tariff policy when there is a potential for a crisis: an increase in demand for goods produced abroad....

We examine the long transition from water to steam power in US manufacturing, focusing on early users of mechanical power: lumber and flour mills. Digitizing Census of Manufactures manuscripts for 1850 to 1880, we show that as steam costs declined, manufacturing activity grew faster in counties...