President Bush offered his vision today on how to shape U.S. global warming policy for the next several decades during a Rose Garden speech that touched on nearly all corners of the contentious issue. "Climate change involves complicated science and generates vigorous debate," Bush said during the nearly 20-minute speech. "Many are concerned about the effect of climate change on our environment. Many are concerned about the effect of climate change policies on our economy. I share these concerns, and I believe they can be sensibly reconciled."