He also announced plans to reaffirm the United States' commitment to work with major economies, and, through the UN, to complete an international agreement that will slow, stop, and eventually reverse the growth of greenhouse gases; he stated, "This agreement will be effective only if it includes commitments by every major economy and gives none a free ride."[166]

Stem cell research and first veto
Federal funding for medical research involving the creation or destruction of human embryos through the Department of Health and Human Services and the National Institutes of Health has been forbidden by law since the passage of the Dickey–Wicker Amendment in 1995.[167] Bush has said he supports adult stem cell research and has supported federal legislation that finances adult stem cell research. However, Bush did not support embryonic stem cell research.[168] On August 9, 2001, Bush signed an executive order lifting the ban on federal funding for the 71 existing "lines" of stem cells,[169] but the ability of these existing lines to provide an adequate medium for testing has been questioned. 