This year we confront and remember two very important days in our history: the 75th anniversary of D-Day and the 50th anniversary of the moon landing. They are connected by a common thread: service and sacrifice.


On June 6, 1944, more than 160,000 Allied troops stormed the beaches of Normandy, France, with the support of more than 5,000 ships and 13,000 aircraft. By the end of that one day, there were 10,000 Allied casualties. But it began the liberation of Nazi-occupied Europe and it would help bring an end to Adolf Hitler’s “war of annihilation” against the Jews.


To commemorate the war’s turning point and honor the heroism and loss of life, world leaders, including President Trump and the Queen of England, have gathered in Portsmouth, England, this week.


British Prime Minister Theresa May read parts of a letter from Captain Norman Skinner of the Royal Army Service Corps to his wife, Gladys on June 3, 1944. Days later, he’d perish along with so many others. He wrote:


“I can imagine you in the garden having tea with Janey and Anne getting ready to put them to bed. Although I would give anything to be back with you, I have not yet had any wish at all to back down from the job we have to do.”


Just 25 years after D-Day, we’d send a man to the moon. It was a mission fraught with danger, but it was an imperative. As President John Kennedy urged in 1961, “We choose to go to the moon in this decade and do the other things, not because they are easy, but because they are hard, because that goal will serve to organize and measure the best of our energies and skills, because that challenge is one that we are willing to accept, one we are unwilling to postpone, and one which we intend to win, and the others too.”


He wouldn’t live to see the fruits of his leadership, but over the next eight years, countless men and women would sacrifice and serve in order to make that vision a reality.


These two pointed events, epic turning points in American and, indeed, world history, are important reminders of what sacrifice and service mean. And not just because if we had lost the war, the world would look starkly, horribly different. Not just because someone else might have beaten us to the moon.


But because sacrifice seems to have lost some of its meaning over time, and modern ideas of public service often stand in stark relief against the selflessness and courage of that time.


Sacrifice is the 1.3 million active duty men and women in the U.S. military and 800,000 reserve forces who volunteer to keep us safe and defend our way of life. It’s not those who avoided enlisting only to dismiss or diminish the service and sacrifice of others decades later.


Sacrifice is a leader who puts the needs of millions of others before his own, who can forgo ego and pride in order to do what he promised he would. It’s rising above pettiness and partisanship for the good of the country. It is not sinking into fetid swamps of vitriol, fear, anger and bigotry just to score political points and console the inconsolable.


Service is running for public office with the explicit and limited goal of serving your neighbors. It is not for building your brand, getting on TV, lining your own pockets or selling books. Whether running for town selectman or president in 2020, it shouldn’t be a publicity stunt or vanity project.


Sacrifice is putting country before party and principles before politics. It is not defending the indefensible, protecting the powerful, or staying silent in the face of injustice just because you’d like to keep your job.


To be sure, examples of real sacrifice and service today are all around us. But among our political leadership, sacrifice and service seem like vestigial organs rendered useless by evolution. Maybe the next generation will do a better job remembering what the Greatest Generation gave us.


S.E. Cupp is the host of “S.E. Cupp Unfiltered” on CNN.