Jon Miller, a professor at Michigan State University, has been tracking scientific literacy for nearly 20 years. He presented his latest findings recently at the annual meeting of the American Association for the Advancement of Science.
The good news: the percentage of Americans with basic scientific literacy has almost tripled in the last two decades. We are now second in the world, ahead of Japan and most of Europe. Only Sweden beats us out.
The bad news: it's not so much that we're so good, but that the rest of the world is so bad. Only 28% of Americans have basic science literacy. As the article points out, citizens are asked to make decisions on issues such as nanotechnology, stem cell research, climate change, etc. We need a basic understanding of the science behind these topics.
However, I must take issue with the last point the professor makes:
Surveys he did starting a year before the 2004 election found that the frequent debates about [stem cell research] ... actually left more voters undecided than they had been before the campaigning began.
I don't think that's a bad thing. In fact, I believe there's a very simple explanation: politicians often take complicated issues and boil them down to simple "soundbite" solutions, designed to get people to agree (and vote) with them. Learning more about any subject makes you appreciate how complex it is, and how very often there are no clear-cut answers.