THE THOUGHT occurs to almost everybody, I would suppose, that politics today is conducted at a lower level than it used to be. Not many voted against William Howard Taft because he was fat or Abraham Lincoln because he was thin. One can't imagine Franklin Roosevelt being judged by how badly he bowled or how convincingly he knocked back a tumble of scotch. Indeed, studies show that the speeches presidents gave a half-century ago were pitched at the 12th-grade level - five grades above the level of speeches given by presidents over the last generation.

Which brings up a paradox. Decade by decade Americans are getting smarter and smarter, and decade by decade our politics is getting dumber and dumber. How can we explain it?

In 1940 six in 10 Americans hadn't gone past the eighth grade. Today, most Americans have attended college. Partly as a result of their added schooling, Americans today are more tolerant of dissent and less racist. But surveys show that increased schooling doesn't correspond to a higher aptitude for civics. To put this bluntly: Americans today are no better informed about politics than their grade-school educated grandparents. With respect to some subjects they are less well-informed.

Like Americans in the 1940s, Americans today barely understand basic facts about our government. Only two in 10 know we have 100 US senators. Only four in 10 know we have three branches of government and can name them. Only a third know that Congress has the power to declare war.

They are no better informed about the identity of the people running the government. Only four in 10 could identify William Rehnquist, the long-serving chief justice of the US Supreme Court, more than two decades into his term. Only two in 10 can name the current secretary of defense, Robert Gates. A Harvard study by Thomas Patterson found that Americans today are less able to articulate the differences between the two major parties than voters in the 1950s.

With respect to complicated issues Americans are at sea. In the 1990s, Michael X. Delli Carpini and Scott Keeter undertook a comprehensive review of surveys measuring Americans' knowledge of politics. The results were shocking. They found that only 14 percent could correctly answer three-fourths of basic questions about foreign policy, barely a passing grade. And foreign policy oddly was one of their best subjects. Only 11 percent could pass a test involving questions about domestic policy, and only 5 percent an economics test. (Americans' best subject was history, though there aren't many history teachers who would find this easy to believe.)

Many political scientists have tried to explain away such results ever since surveys in the 1940s began turning up evidence of Americans' gross ignorance about politics. These apologists argue that Americans use shortcuts to compensate for their lack of knowledge. A voter, for example, who does not follow the daily news may nonetheless decide that he should vote for Candidate X because his local newspaper endorsed X and he generally agrees with the positions the paper takes.

Unfortunately, what the polls show is that Americans cannot make up for their lack of basic knowledge even if they shrewdly employ shortcuts. The harsh truth is that ignorant voters are sitting ducks for wily politicians. This is why millions were so easily misled when the Bush administration dropped hints that Saddam Hussein played a role in the Sept. 11, 2001, attacks. One study by the University of Maryland found that nearly 60 percent of Americans were convinced that Hussein was helping Al Qaeda when we undertook our invasion. A majority based their support for the war on this flagrant misunderstanding.

Why hasn't education helped voters become smarter about politics? Television is a big part of the explanation. Once television replaced newspapers as the chief source of news, this happened around 1965, shallowness was inescapable as Americans began judging politicians by how they looked and acted. Another factor was the collapse of the traditional two-party system and unions. Once voters stopped taking their cues from party and labor bosses, they were largely on their own as they sorted through the complicated choices they face.

If politicians were angels, we wouldn't need smart voters. But they aren't. One of the most pressing issues of our times, though few talk about it, is therefore the acknowledgement of the limits of contemporary voters and strategies to make them smarter.

Rick Shenkman is the author of "Just How Stupid Are We? Facing the Truth About the American Voter."

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