WASHINGTON — US President Joe Biden marked Monday evening 500,000 coronavirus deaths in the US, saying "today, we mark a truly grim, heartbreaking milestone: 500,071 dead. "That"s more Americans who have died in one year in this pandemic than in World War One, World War Two, and the Vietnam War combined. That"s more lives lost to this virus than any other nation on Earth," Biden said in remarks at the White House. Biden honored the 500,000 American lives lost to coronavirus on Monday, speaking of the collective grief of a nation and in personal terms. "The people we lost were extraordinary. They spanned generations," he said. "Just like that, they took their final breath alone, in America." He added, "Today, I ask all Americans to remember: Remember those we lost and those who are left behind.” "But as we all remember, I also ask us to act. To remain vigilant, to stay socially distanced, to mask up, get vaccinated when it"s your turn," he stressed. "We have to fight this together, as one people, as the United States of America. That"s the only way we"re going to beat this virus," Biden noted. Biden, along with Vice President Kamala Harris, observed a moment of silence at sunset and a candle-lighting ceremony for the 500,000 coronavirus deaths. He also ordered all flags on federal property to be lowered at half-staff for the next five days. In a Proclamation, Biden said "on this solemn occasion, we reflect on their loss and on their loved ones left behind. We, as a Nation, must remember them so we can begin to heal, to unite, and find purpose as one Nation to defeat this pandemic." Biden spoke from experience when it came to describing the grief of losing a loved one. "For the loved ones left behind: I know all too well. I know what it"s like to not be there when it happens. I know what it"s like when you are there holding their hands, there"s a look in their eye and they slip away," Biden said. “I know that when you stare at that empty chair around the kitchen table it brings it all back no matter how long ago it happened, as if it just happened that moment," he added. The president also expressed optimism, telling Americans: "We will get through this, I promise you." "We ask you to join us to remember. So we can heal. To find purpose, and the work ahead to show that there is light in the darkness," Biden said. "This nation will smile again. This nation will know sunny days again. This nation will know joy again." He also warned of the costs of complacency in the face of such staggering loss. "While we"ve been fighting this pandemic for so long, we have to resist becoming numb to the sorrow," Biden said. "We have to resist viewing each life as a statistic, or a blur, or on the news." — Agencies