Wade Allison, Emeritus Professor of Physics, Keble College, Oxford University, UK: This article discusses the importance of plentiful, reliable energy for humanity. It includes the topic of carbon dioxide from fossil fuels reportedly going to cause serious climate change problems. This leads to recommendations to dramatically cut back on fossil fuels and quickly switch to nuclear. Several things may stand in the way: 1) Nature. It may remain the primary cause of climate change. Any energy source we select may have little influence on future climate change. If it gets colder, we will need lots of energy from fossil fuels and nuclear. 2) The world will not be ready for a long time to implement nuclear like Canada, France and the USA did. Bad government, corruption, egotism, weak economies, inferior education will stand in the way. 3) When planning globally, it is essential to have global solutions that work.