US President Joe Biden marked the 80th anniversary of D-Day on Thursday by saying "we will not walk away" from the defence of Ukraine and allow Russia to threaten more of Europe.
"To surrender to bullies, to bow down to dictators, is simply unthinkable," he said during a ceremony at the American cemetery in Normandy. "If we were to do that, it means we'd be forgetting what happened here on these hallowed beaches."
D-Day was the largest amphibious assault in history, and Biden called it a "powerful illustration of how alliances, real alliances make us stronger". He said that was "a lesson that I pray we Americans never forget".
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Biden's comment was a reminder that US commitments around the globe hang in the balance in this year's White House election. Former President Donald Trump, Biden's likely opponent, has said he would not defend European allies that are "delinquent" in their own defence spending.
Speaking about the American troops that stormed Normandy's beaches on June 6, 1944, Biden said "let us be worthy of their sacrifice".
"We must remember that the fact that they were heroes here that day does not absolve us of what we have to do today. Democracy is never guaranteed. Every generation must preserve it, defend it and fight for it. That's the test of the ages."
Before Biden's remarks, French President Emmanuel Macron told US veterans that "you came here because the free world needed each and every one of you, and you answered the call".
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Macron awarded the Legion of Honor to several of them, and he kissed them on each cheek as he pinned on their medals. Biden followed with handshakes and embraces.
Earlier, Biden and first lady Jill Biden met with more than two dozen American veterans near Omaha Beach, where the fiercest D-Day fighting took place. Those who could stand were helped out of wheelchairs to pose for photos. Most shook hands with Biden or saluted; one hugged him.
Biden told a veteran that "you saved the world". The president led the audience in singing happy birthday to another. Steve Spielberg and Tom Hanks, the Hollywood heavyweights behind movies and television shows about World War II, were nearby.
When Army veteran Robert Gibson approached, the first lady clutched his arm to help him stand next to the president as they shook hands.
"Don't get old," the 100-year-old man from New Jersey joked to the 81-year-old president, who was a toddler on D-Day.
This anniversary of the invasion is a particularly somber one because it will be among the last with living veterans. The youngest survivors are in their late 90s. Biden met one veteran who is 104.
In an interview with The Associated Press a few days ago, Gibson described himself as "living on borrowed time".
He was part of the second wave of troops that landed on Utah Beach. Gibson said he expected this year would be the last anniversary ceremony that he could attend, but he was pleased to be back one more time.
"I want to see the beach again," he said.