The Law of Unintended Consequences

The mongoose was introduced to Hawaii in order to control the rats (which were eating the sugar cane used to make rum). It didn't work out very well - mongeese are daylight-loving creatures while rats are nocturnal - and the mongeese trashed the native species in Hawaii.

Likewise, the U.S. government has subsidized ethanol production for years. But the Congressional Budget Office says this week that increased ethanol use is responsible for about 10 to 15 percent of the rise in food prices from 2007 to 2008, and only reduced greenhouse gas emissions from the transportation sector by less than 1 percent.

Given that implementing "solutions" without fully understanding the consequences often cause more harm than good, Obama 's consideration of geoengineering the planet to fight global warming should be subjected to rigorous debate to make sure that it will actually be a good thing.