Today is a special day for the United States, one that commemorates the 75th anniversary of one of the most important battles in this nation’s history — D-Day.

It’s also a sad day, as it may be the last major commemoration attended by the brave men who stormed the beaches of Normandy on June 6, 1944, to begin an Allied invasion that was the beginning of the end of World War II.

Today’s anniversary is a milestone that is expected to represent the last large gathering of D-Day veterans around the globe. Those men who are still alive are in their mid-90s now.

On a broader scale, about 496,000 of the 16 million Americans who served in WWII are still living, as of 2018, according to projections by the U.S. Department of Veterans Affairs. An estimated 348 WWII veterans die every day in the U.S. In Massachusetts, about 13,000 WWII veterans are still living.

Pretty soon, they all will be gone. We hope their heroism can live on once they pass, but it becomes more difficult as time marches on. That’s why it’s imperative on the rest of us to carry forward their stories, remember the history they forged and the sacrifices they and their fallen comrades made.

The National D-Day Memorial in Bedford, Virginia, is doing its part. The organization is observing the 75th anniversary with six days of ceremonies, displays, interviews, and much more. The memorial is based in this small Virginia community that lost 20 of the 32 men it sent to the invasion — the highest per capita D-Day losses in the country.

“Over time, grief gave rise to solemn pride and deep commitment to ensuring the story of D-Day and its costs and consequences were not lost on future generations,” the National D-Day Memorial website states.

The memorial’s motto — “Commemorating Their Valor, Fidelity, and Sacrifice” — places education at the center of its mission, with memorial organizers saying “The Final Salute,” the 75th anniversary of D-Day, is the organization’s biggest educational undertaking yet.

“The Final Salute” will include a gathering of veterans and the general public at the nation’s memorial, where the story of ordinary people in extraordinary moments will unfold.

The D-Day invasion is also at the heart of the National WWII Museum, which opened in 2000 in New Orleans as the National D-Day Museum. This is a place to get lost in all things WWII, with a campus that includes five pavilions on a 6-acre site, with an expansion in the works.

“Sadly, the ranks of WWII veterans have diminished as the Museum has grown,” the museum’s website states. “The reality of the WWII generation’s march into history fuels the Museum’s goals: to finish its campus while there are still WWII veterans to visit it, and to propel our WWII collections and educational expertise to the world’s history enthusiasts, students, educators, and scholars.”

So on this 75th anniversary of the D-Day battle, we collectively should resolve to work harder to make sure this history isn’t lost when the last veteran of that battle departs.