When I was in college taking engineering back during the 1950's everyone thought that the world would run out of oil in 20 years. I recall bull sessions in which I speculated, to a lot of derision, that the world would not run out of oil during my lifetime. At that time people were hoping that CO2 emissions would cause enough warming to stave off the imminent ice age. We were more worried about the Soviet Union than climate disaster. During the 1970's people got worried about the shortage of energy and the US started an alternative energy program. I did research for the company I worked for, and we decided that there was no shortage of energy, so did not pursue alternative energy. (Many rent-seeking companies did pursue it because of the government subsidies, rather than expectation of success.) Now we are once again worried about energy, but this time not so much with a shortage, but with concerns about CO2 emissions that computer models predict will cause catastrophic heating of the world. There is a lot wrong with the computer predictions, such as inability to accurately model the hydrological cycle, as I have discussed before. But, the scaremeisters have carried the day with politicians, who recognize the issue as the path to increased government control over people, something all politicians crave. Here is a good discussion of the situation, including why Obama's plans are doomed to failure. One factoid people should consider: an adult breathes out about 0.4 tons of CO2 each year. If each persons allotment is 2 tons per year in 2050, as would be required by Obama's plan, we won't be eating much beef, or even riding a horse unless we have built a lot of nuclear power plants (which Obama doesn't want).