WASHINGTON (AP) — President Joe Biden marked Memorial Day with a pledge that the country would continue the work of the nation’s fallen toward creating a more perfect union, “for which they lived, and for which they died for.”

Delivering remarks at a solemn remembrance ceremony at Arlington National Cemetery, Biden said each generation must ensure the sacrifice of the country’s service members is not in vain.

“Freedom has never been guaranteed,” Biden said under gray skies in the memorial amphitheater. “Every generation has to earn it, fight for it, defend it in the battle between autocracy and democracy, between the greed of a few, and the rights of many.”

He added: “On this day, we came together again to reflect, to remember, and above all, to recommit to the future they fought for, a future grounded in freedom, democracy, opportunity and equality. Not just for some, but for all.”

Before the ceremony began, Biden, joined by Vice President Kamala Harris and Defense Secretary Lloyd Austin, placed a wreath at the Tomb of the Unknown Soldier.

In his remarks, Biden invoked the anniversary this week of the death of his son Beau, who served in Iraq and later died from brain cancer that the president attributes to his time stationed near toxic burn pits, to highlight the importance of honoring the service of those who came home with injuries, in addition to the dead.

“Last year, the VA delivered more benefits and processed more claims than ever in our history,” Biden said, crediting the PACT Act which grants automatic coverage for certain health conditions suffered by veterans by presuming they result from their military service. “For too long after fighting for our nation, these veterans had to fight to get the right health care, to get the benefits they had earned, not anymore.”

Biden began the day hosting a breakfast at the White House for administration officials, military leaders, veterans, and Gold Star family members.