A reduction in income tax rates generates substantial dynamic responses within the framework of the standard neoclassical growth model. The short-run revenue loss after an income tax cut is partly - or, depending on parameter values, even completely - offset by growth in the long-run, due to the resulting incentives to further accumulate capital. We study how the dynamic response of government revenue to a tax cut changes if we allow a Ramsey economy to engage in international trade: the open economy's ability to reallocate resources between labor-intensive and capital-intensive industries reduces the negative effect of factor accumulation on factor returns, thus encouraging the economy to accumulate more than it would do under autarky. We ...