AS I sit down to write my last World lines column, I cannot help thinking how much the world has changed since I began the column in 2007. The global economy has been trashed by the same sort of short-sighted greed that mirrored the political actions of a US administration that too often rushed for short-term political gain at the expense of long-term international stability.
Back in 2007 I would never have imagined that the international banking system was on the brink of collapse, but I would also never have dared predict the dramatic changes that have recently taken place in Washington DC, in particular the role of science in making rational public policy.
The first rule for making accurate scientific predictions is "garbage in, garbage out". It is the same with public policy. As we have learned the hard way, sound public policy relies on the input of sound science, whether that involves the mathematics of the marketplace or the physics of energy production and climate change.
My second World lines column called for a scientifically literate president. We finally have one. After almost a decade of erosion of scientific integrity in Washington, President Barack Obama announced this month that the rules have changed, promising to base "public policies on the soundest science". As he put it, referring to the policies of the past administration, "our government has forced what I believe is a false choice between sound science and moral values".
A key example of the new regime is Obama's stance on stem cells. Many of us involved in his presidential campaign predicted that he would lift restrictions on stem cell research in the week after his inauguration. He didn't. Wisely, he has shown that he wants to make decisions in a measured fashion, rather than rashly responding to gut instinct or emotion. He has directed the National Institutes of Health to develop revised guidelines on federal funding for embryonic stem cell research within 120 days. What is most significant about this announcement is not merely that decisions on this kind of research have been returned to those who best understand the scientific issues involved, but that sound science will once again form the basis of policy at a national level. He has also directed the White House Office of Science and Technology Policy to "develop a strategy for restoring scientific integrity to government decision making".
During the Bush administration, government scientists saw their recommendations censored or distorted by the White House, advisory committees were stacked with political appointees without appropriate credentials or knowledge, and statements on issues ranging from the environment to sex education and disease control misrepresented the facts.
Obama has taken a huge step toward rebuilding trust, but I don't want to end this column's run with dreamy-eyed claims that we have reached nirvana. Many programmes that fly in the face of empirical data remain, such as the government-funded abstinence-only sex-education programmes. We are also still spending billions of dollars each year on a contentious missile defence system that doesn't work. And I am worried about the efficacy of Obama's plan to throw money at the US science establishment to be spent in a two-year time frame. It needs to be backed up by a longer-term funding plan.
It has been a wild ride, but the past year's unexpected political and economic events remind me of why I have always valued the empirical nature of science. Nature often surprises us more profoundly than our imagination can predict, which is why it is so important to be guided by evidence rather than by edicts imposed from on high.
Lawrence Krauss is director of the Origins Initiative at Arizona State University in Phoenix