As co-blogger Jonathan Adler points out, a recent Rassmussen survey shows that voters are incredibly ignorant about the Obama administration's proposal to fight global warming through a "cap and trade" program. The poll finds that only 24% of American adults understand that the plan has to do with "environmental issues"; 29% believe that it is a "Regulatory reform for Wall Street" and 17% answered that it is a type of "health care reform."
Obviously, knowing that cap and trade is an environmental policy proposal is only a bare minimum level of knowledge. One would need to know a lot more to really understand the pros and cons of the idea. For example, voters should have some understanding of how much it will really reduce global warming, what the economic costs will be, and how well the policy stacks up against alternatives such as a carbon tax. In addition, widespread public ignorance of even the most basic facts about cap and trade exacerbates the danger that the policy can be used as a tool for rent-seeking by narrow interest groups at the expense of the general public.
To avoid misunderstanding, I should note that I think that global warming is a genuine and serious problem (though I lack the scientific knowledge to know for sure). And I tend to agree with Jonathan that a carbon tax is preferable to cap and trade as a policy option for reducing warming. One of the advantages of a tax is that it's relatively easier for voters to understand.
Unfortunately, public ignorance about policy goes far beyond cap and trade. It extends to many other issues. As I have argued in various articles (e.g. here and here), political ignorance is actually rational behavior for most voters. But it is a serious problem for modern democracy, one that will only get worse as government continues to expand in size and complexity.
UPDATE: It's worth noting that we can't be sure that even the 24% really know that cap and trade is an environmental policy proposal. Some of the respondents who picked the right answer might have done so by random guessing. Survey researchers have shown that random guessing on surveys is actually quite common. For example, respondents will often express opinions about completely nonexistent bills made up by researchers rather than admit that they haven't heard of them.