The joint dynamics of US net output, consumption, and (the market value of) foreign assets and liabilities, characterized empirically following Lettau and Ludvigson (2004), is shown to be consistent with current account theory. US consumption is virtually insulated from transitory shocks, while these contribute to variations in net output and gross foreign positions—consumption is smoothed against temporary fluctuations in returns. A single permanent shock—naturally interpreted as a supply shock—raises consumption swiftly while causing net output to adjust gradually. This leads to persistent, procyclical external deficits, while moving gross assets and liabilities in the same direction. JEL: E21, E23, F32, F34

The short-run effects of fiscal policy depend not only on current tax and spending choices, but also on expectations about future policy adjustment. While general equilibrium models typically restrict medium-term adjustment to taxation, we highlight the importance of government spending dynamics. First, we provide time series evidence for the United States suggesting that an exogenous increase in government spending prompts a rise in public debt, followed over time by a reduction in spending below trend. Second, we show how expected spending reversals alter the short-run impact of fiscal policy in a new Keynesian model, bringing it closer in line with the evidence.