The idea that government policies have unintended consequences has become a fixture of political argument, indeed a cliché. One can hardly get through a day's newspaper editorials without encountering it with respect to something in the news--the TARP bailouts, the North Korea bailouts, executive pay caps, local issues such as the drinking age and the driving age. "Unintended Consequences" is the title of many recent books--by Deepak Lal on the role of culture and politics in economic performance, by Peter Galbraith on the Iraq War, others on housing policy, drug policy, military history, technological change, a novel about gun control, even a Spider Man comic book. If you go to the blogosphere you will find almost a genuine google of postings based on the idea.
The phenomenon is a curious one if you take the term literally. Virtually every action of any consequence, private as well as public, has some consequences that were not part of the purpose of the action. If you attend a lecture at the American Enterprise Institute you may make an important contact but miss an important phone call or email. The human drama is replete with best laid plans going awry. Looking at things through the other end of the telescope, virtually every event has innumerable but-for causes, all the way to that Kansas tornado whose path is affected (according to chaos theory) by the flapping of a butterfly's wings in China. The manipulation of but-for causation is a staple of time-travel science fiction. Why should it be interesting and important that a government policy had consequences that were not intended?
Christopher DeMuth is the D. C. Searle Senior Fellow at AEI.