A society can make progress only if its young people know of the progress their country has made so far. In America, that means fourth-graders should be able to identify Abraham Lincoln – only 9 percent can. High school seniors must know about the Supreme Court’s 1954 ruling Brown v. Board of Education – only 2 percent do.

Such statistics are particularly worrisome because today’s 12th-graders will be able to vote in next year’s elections.

Most of these fledgling citizens and future leaders haven’t fared well on a national “report card” issued every few years about how well students grasp civics and history.

In the latest scores from the National Assessment of Educational Progress, just 12 percent of high school seniors are proficient in US history while 24 percent measure up in civics. And of all the subjects tested under NAEP since 1994 – math, reading, science, writing, geography, civics, history – students do the worst in history.

In the 2010 test, some progress was found among eighth-graders, especially blacks and Hispanics, since 2006. And ever since the NAEP began in 1994, fourth-graders have shown a healthy gain in history scores. But that may reflect improvements in reading skills, experts say.

By the 12th grade, students score the worst on history compared with earlier grades, with more than half not reaching even basic knowledge. (The test categories for history include democracy, culture, technology, and the US role in the world.)

Fixing this problem isn’t easy. Education in the United States has become focused on developing marketable skills for scarce jobs and less on the skills of citizenship. The 2002 No Child Left Behind Act has forced schools to focus almost solely on math and reading, which often leaves history and civics in the dust. As a result, most fourth-graders spend less than two hours a week on social studies in the classroom.

This curriculum gap may be one reason for the generally declining rate of voting among young people. And one recent survey found most 18-to-29-year-olds could not peg the unemployment rate (9 percent) within five percentage points.

Such glaring ignorance shows up in politics, too. Sarah Palin got history wrong recently by saying Paul Revere’s ride was meant to warn the British – about the British.

Americans put themselves at the mercy of political spin if they don’t understand the currents of their history. Politicians will only raise more money to buy more half-truth ads to fool the least knowledgeable of voters. (They also make themselves more beholden to campaign donors, corrupting government.)

Knowing the trials and triumphs that made America it is today are essential if it is to endure more trials and achieve more triumphs.