ECCLESIASTES 7:10: Robert Samuelson argues against drawing apocalyptic conclusions from Americans' ignorance of history:

I reject the alarmist notion that ignorance threatens our social cohesion or democracy by cutting us off from the roots that define the American experience.
If that were so, we would have foundered long ago. Perhaps there was some golden age when most Americans knew their history. It seems unlikely, but without good survey data before the 1930s, we cannot know. Since then, we do know; we're dummies.
"Our comparisons of recent surveys with polls from the 1940s and 1950s suggest that there's been no overall increase in knowledge despite enormous increases in education," says political scientist Scott Keeter, co-author with Michael X. Delli Carpini of "What Americans Know About Politics and Why It Matters." A 1986 poll found that only 49 percent of Americans knew that the United States was the only country to have used nuclear weapons in war. In a 1989 survey, only 63 percent correctly identified Franklin Delano Roosevelt as a Democrat. Ugh.
To blame inept schools and lazy students is to miss the larger cultural failing. I grew up in the 1950s. My parents didn't discuss the Great Depression, which was history only two decades old, let alone the Revolution or Civil War. They probably were typical.
... The "greatest generation" knew why it was fighting, even though it was as ignorant of history as its children and grandchildren, perhaps more so. In 1943, a Gallup poll found that about 30 percent had never heard of the Bill of Rights and fewer than 23 percent could identify it as the first 10 amendments to the Constitution; the rest were confused about what it was.
In 1942, Elmo Roper -- a pioneer in opinion surveys -- wrote (in his pre-politically correct prose): "A great many of us make two mistakes in our judgment of the common man. We overestimate the amount of information he has; we underestimate his intelligence. . . . During my eight years of asking the common man questions about what he thinks and what he wants I have often been surprised . . . that he has less information than we think he should have. . . . But I have more often been surprised . . . that, despite his lack of information, the common man's native intelligence generally brings him to a sound conclusion."

As a history-obsessive who once considered pursuing an academic career in the field, I think that Samuelson is absolutely right about the (lack of) consequences of Americans' ignorance. And the stats cited by Samuelson regarding the knowledge of the "greatest generation" illustrates one of the most important lessons of history: Nostalgia is for the weak-minded. Nine times out of ten, the sentiment of "things were so much better back [insert time of speaker's childhood]" is wrong, and the tenth time is usually overstated.