Economists have been more influential over the past 15 years than at probably any other time in history. The policies of central planning, dirigisme and import substitution, which many newly independent countries adopted in the 1950s and 1960s, could be labeled as the ideas of communists, Fabian socialists and nationalists, not trained economists. The policies of deregulation, privatization and trade liberalization (the so-called Washington Consensus) that countries adopted in the 1980s, supposedly marked the victory of professional economists over populist politicians.
The paradox is that this was no victory for economics. Indeed, the past two decades have proved dismal for the practice of the "dismal science." With few exceptions, countries in which the US-educated economic technocracy gained the upper hand performed worse than they did prior to the 1980s.
Latin America's stalled and stagnant economies, which embraced the Washington Consensus more than most, stand out as "exhibit A." The biggest development successes in recent years have been in places like China and Vietnam, where Western economic ideas, to the extent that they were considered at all, lost out to more practically oriented policy-makers.
The puzzle is not "why did economics fail us?" but "why were economists so overconfident?" After all, much of the Washington Consensus cannot be deduced from proper economic analysis. Any graduate student in economics knows that deregulation, privatization and trade liberalization cannot be expected to produce economic benefits without a long list of unlikely conditions being satisfied.
Moreover, there is nothing in economic theory that should have made economic technocrats think that Anglo-American institutions of corporate governance or "flexible labor markets," to pick just two examples, produce unambiguously superior economic performance.
What passed as state-of-the-art thinking on economic policy turns out to have been based on some crude rules of thumb. More often than not, the advocacy of simple panaceas was based on one or more of the following pathologies.
South Korea has done better than North Korea, and Burma's path is hardly one that leads to prosperity. Therefore we know that markets do better than central planning, and that foreign trade is better than autarky. But it takes a huge leap of faith to conclude from this that one can't go wrong by deregulating, privatizing and opening domestic markets as much as possible. Analysts who focused only on those elements of China's or South Korea's experience that fit their beliefs missed the larger story that these countries were undergoing massively heterodox experiments.
Implicit political theorizing
Economists who become policy advisers are great fans of simplicity, uniformity and arm-length relations between government and the private sector, not because of economic theory or empirical evidence, but because of unexamined and untested assumptions. Governments, they believe, are run by crooks, so tie their hands; bureaucrats are beholden to rent-seeking private agents, so ensure non-discretion and apply uniform taxes and incentives; domestic political systems cannot be trusted, so import laws and institutions from abroad; external influences are always more benign than domestic ones, so ensure maximum openness to international trade and investment. Economists ended up practicing public administration without license.