A quarter of Americans don't know that D-Day occurred during World War II.

That punch in the gut is just one of the findings from a newly released survey about historical amnesia. On the 70th anniversary of one of the most important days in American history, it's imperative that we as a nation reflect on the sacrifices of those who were at D-Day and take stock of whether we are honoring their legacy.

The findings suggest we're not.

Just 40 percent of Americans know that June 6 is the anniversary of D-Day and not even half know that the president at the time was Franklin D. Roosevelt, according to the multiple choice survey. Among college graduates, the picture looks only slightly better: 55 percent know today is the anniversary and 57 percent know Roosevelt was president.

The American Council of Trustees and Alumni has been documenting this growing trend in historical illiteracy for years, and the culprit is our nation's education system. Far too often, it fails to prepare students with the knowledge they'll need for informed citizenship.

Even after college, many students don't have a grasp on the basics. Another survey found that only 17 percent of college graduates knew the effects of the Emancipation Proclamation and only two in five knew the Battle of the Bulge occurred in World War II.

It's not surprising, considering that only five of the top 50 public universities in the country require even one survey course on American history or government. Similarly, it's not required at a single top liberal arts institution except for the military academies.

Is it any wonder why we are in this crisis when students can graduate from our most prestigious universities with the historical knowledge of a 12th grader?

It wasn't always like this; For most of our history it wasn't a question whether a college student would study the past. Over 98 percent of college-educated senior citizens know D-Day occurred during World War II, but only 71 percent of recent college graduates said the same.

For years colleges have loosened curricular requirements by allowing niche courses to take the place of American history courses.

American history courses at Michigan's Oakland University can be swapped with "Foundations of Rock," "Dance in American Culture," or "Human Sexuality."

At the University of California-Berkeley, it can be replaced with the "History of Avant-Garde Film" or "Dutch Culture and Society: Amsterdam and Berkeley in the Sixties."

And at the University of Colorado, American history can be replaced with "America Through Baseball," "Horror Films in American Culture" or the indelicately titled "Wops and Dons to Movers and Shakers: The Italian-American Experience."

The story is the same nationwide — probably including your alma mater or that of your children. While these courses may have a lot to offer, they shouldn't replace foundational knowledge that employers and the public demand. And during a time when almost one in 10 college graduates believe the D-Day invasion took place at Pearl Harbor, it's time for some academic prioritization.

And, it's not just American history that is being forgotten.

The "What Will They Learn?" study examines every public college in America — and hundreds of private institutions, too — to determine whether students take courses in seven key subjects: math, literature, composition, science, economics, foreign language and American history/government.

Only 22 institutions out of nearly 1,100 get an "A" rating for requiring at least six of the seven fundamental courses. That's just 2 percent of institutions that are meeting even basic requirements.

American education must change, and for that to happen the American people must demand change. How can American students compete globally when they're more familiar with Snapchat than the Fireside Chats? And how can they assume control of our nation when not even two in five know the term lengths of their senators and representatives?

In 1787, our fledgling nation had a new Constitution, out of which — against all odds — would rise one of the most successful political experiments that mankind had ever known. As Benjamin Franklin left Independence Hall, a woman asked him a question.

"Well, Doctor, what have we got — a republic or a monarchy?"

Following the months of contentious deliberation over the Constitution and the years before that of fighting for the right to be free, Franklin replied: "A republic, if you can keep it."

Now we must ask ourselves: Can we?

— Daniel Burnett is press secretary of the American Council of Trustees and Alumni, a higher education nonprofit dedicated to academic excellence.