What we knowPresident Joe Biden joined French President Emmanuel Macron, Britain's King Charles III and other dignitaries to mark the 80th anniversary of D-Day, when the Allied forces launched a surprise attack that helped liberate Europe from Nazi Germany."Democracy is never guaranteed," he told the assembled crowd at the Normandy American Cemetery as he honored the veterans who fought in the defining World War II battle and helped defeat Nazi Germany. He went on to praise NATO’s strength and unity, drawing an implicit contrast with his Republican rival, Donald Trump, who aides say considered withdrawing from the alliance. Leaders traveled from around the world to attend commemorations in northern France, but the real stars of the occasion were the handful of remaining veterans. About 150 American veterans who took part in the Normandy landings were expected to attend the ceremonies, which could be the last major milestone for many. Western leaders are also confronting a shattered postwar peace, with Russia waging a new war in Europe, and the far-right on the march.