GEOFF BENNETT: Welcome to the "NewsHour."

President Biden is in Normandy, France, today to mark 80 years since the D-Day landings ushered in the bloody final chapter of World War II.

But, today, he also pointed to the urgent threats once again raging in Europe, this time in Ukraine.

AMNA NAWAZ: And while the specter of that brutal war haunts Europe now, it was for the hundreds of veterans of the longest day that these ceremonies were most poignant.

Both Mr. Biden and French President Emmanuel Macron extolled the uncommon valor of ordinary men and women who accomplished the extraordinary some 80 years ago.

Today, we are as from D-Day as D-Day was from the height of the American Civil War.

But the history made on those bluffs above the wide beaches of Normandy feels closer still.

Here's Malcolm Brabant in Northern France.

MALCOLM BRABANT: Eighty years ago, these veterans counted their life expectancy in minutes, yet here they were back at Omaha Beach 100 years old or thereabouts.

Among those greeting President Biden, who was 18 months old on D-Day, was 99-year-old Staff Sergeant George Mullins, of the 101st Airborne.

He landed on Utah Beach in a glider and fought through Europe for 11 months until he reached Hitler's eagle's nest in Berchtesgaden, Germany.

The president drew on the heroism of the Greatest Generation and the liberation of France to implicitly warn against the isolationism of Donald Trump and to send a message to Russia's President Putin.

JOE BIDEN, President of the United States: The struggle between a dictatorship and freedom is unending.

Here in Europe, we see one stark example.

Ukraine has been invaded by a tyrant bent on domination.

MALCOLM BRABANT: The audience was unaware that Ukraine's President Zelenskyy was in Normandy.

JUSTIN TRUDEAU, Canadian Prime Minister: It's the Ukrainian president (OFF-MIKE) right now.

Thank you very much.

(LAUGHTER) MAN: You are the savior of the people.

VOLODYMYR ZELENSKYY, Ukrainian President: No, no, no.

You, you saved Europe.

JOE BIDEN: The United States and NATO and a coalition of more than 50 countries standing strong with Ukraine, we will not walk away.

(APPLAUSE) MALCOLM BRABANT: Invoking the veterans' courage and sacrifice, the president said it would be a betrayal of their example to abandon Ukraine.

JOE BIDEN: Remember, the price of unchecked tyranny is the blood of the young and the brave.

MALCOLM BRABANT: France's President Emmanuel Macron concentrated on the valor of America's warriors, 11 of whom were awarded the Legion of Honor, the French equivalent of a knighthood.

EMMANUEL MACRON, French President Here you come to join your efforts with our own soldiers, and to make France a free nation.

And you are back here today, at home, if I may say.

MALCOLM BRABANT: One-hundred-and-one-year-old engineer Calvin Shiner from Texas, first invaded Italy, then France, carried on through to Germany, and, in the dying months of the war, he worked on reconstruction.

The abiding message from this historic day was that every man had a tale to tell and we have a responsibility to pass it on.

This cemetery possesses a story of valor kept secret for decades.

Here lies Sergeant Eugene Fuller who tried to neutralize a German howitzer shelling Allied-held beaches.

He hid close by and radioed the gun's position to American planes.

Their bombs fell short and Fuller was killed a week after he displayed true gallantry during the landings and beyond.

As you can see from the gravestone, Eugene Fuller was not the sergeants real name.

He took an alias, or a nom de guerre, to protect himself, just in case he was captured by the Nazis and tortured.

His real name was Eugen Von Kagerer-Stein.

And the cross on the grave might lead you to believe that he was a Christian, but he wasn't.

He was an Austrian Jew who belonged to a secret group of commanders called X Troop, made up of scores of Jews who escaped from Hitler's Third Reich and sought vengeance.

This band of predominantly German and Austrian Jews was transformed into a fearsome commando unit by Captain Bryan Hilton-Jones, a tough mountaineer.

Earlier this week, in North Wales, Hilton-Jones, daughter, Nerys Pipkin, unveiled a plaque commemorating X Troop.

NERYS PIPKIN, Daughter of X Troop Commander Bryan Hilton-Jones: They were selected out of over 350 applicants for their intelligence, their knowledge, their fluency of German, and their absolute hatred of Hitler.

KIM MASTERS, Daughter of X Trooper Peter Masters: For men like my father, the motivation was that this was a personal war.

MALCOLM BRABANT: X Trooper Peter Masters revealed his comrades' exploits in a book called "Striking Back."

His daughter is Kim Masters, editor at large of "The Hollywood Reporter."

KIM MASTERS: My father wanted nothing more than to fight Germans, and D-Day was the big one.

MALCOLM BRABANT: Eighty years ago, on D-Day, inspired by the lone piper Bill Millin, whose legendary courage was commemorated today, X Trooper Peter Masters waded ashore.

He had a bicycle on his back and was ordered to pedal several miles through hostile territory to Pegasus Bridge, a key allied objective taken earlier by British paratroopers.

KIM MASTERS: My father had the hero's story, and it was really important to him to send the message that Jews didn't go, as he would put it, like lambs to the slaughter, that they fought back.

This group of men in the British army undertook a very hazardous duty.

They had a battle to win.

I mean, they were fighting not only for the world, but for themselves.

MALCOLM BRABANT: Balcombe in Southern England is where Fuller lived with his wife and young son before D-Day.

Villagers are constantly reminded of the horrors of war.

Their community hall contains unique frescoes depicting the trenches of World War I.

In Remembrance Corner of the parish church, Sergeant Eugene Fuller's true identity can be found.

Until now, his story wasn't common knowledge.

But, finally, this coming Sunday, the congregation will learn that Eugen Von Kagerer-Stein fought back.

Today's anniversary has been the emotional highlight for thousands of World War II enthusiasts who've flooded the battlefields with their vintage vehicles and uniforms.

But Brent Mullins, who heads the museum of the American G.I.

in College Station, Texas, is troubled by what he perceives as saber-rattling over Ukraine.

BRENT MULLINS, Museum of the American G.I.

: It's as if the politicians haven't learned a thing about diplomacy and brinksmanship.

And I'm afraid, just like in all the previous wars, that the United States is going to be drug into it.

("TAPS" PLAYING) MALCOLM BRABANT: "Taps," the bugle call that signals lights out, on a day that will live in the memory for eternity.

For the "PBS NewsHour," I'm Malcolm Brabant in Normandy.