This paper studies a model of random technical progress where technology diffuses at realistically slow rates. It fits smooth trends to the sum of GDP series generated by this model and series representing transitory, or cyclical, fluctuations. Detrended GDP is then largely unrelated to technical progress. The detrending method proposed by Rotemberg (1999) reconstructs cyclical variations somewhat more accurately than the HP filter. With sufficiently slow diffusion it is also more accurate than a method based on VARs fitted to hours and GDP growth. Consistent with the model’s predictions, permanent shocks initially depress both hours and output in these VARs.

In public discussions of policy, evidence that import‐competing sectors earn low or falling incomes is often used to argue for protection. This paper rationalizes the apparent effectiveness of this argument in both direct and indirect democracies. In direct democracies, a small degree of voter altruism leads to protection in the specific factors model when the import‐competing sector earns little. Similarly, voter altruism creates an incentive in representative democracies for self‐interested parties to present evidence to legislators on the income of import‐competing factors. This leads to a theory in which campaign contributions buy access to legislators rather than buy votes.