US President Joe Biden honored on the eve of the 20th anniversary of the Sept. 11 attacks the 2,977 people who lost their lives. "To the families of the 2,977 people from more than 90 nations killed on Sept. 11, 2001, in New York City, Arlington, Virginia, and Shanksville, Pennsylvania, and the thousands of more that were injured, America and the world commemorate you and your loved ones," Biden said in a video. He added, "We honor all those who risked and gave their lives in the minutes, hours, months and years afterwards. It"s so hard, whether it"s the first year or the 20th." "No matter how much time has passed, these commemorations bring everything painfully back as if you just got the news a few days ago. In the days that followed Sept. 11, 2001, we saw heroism everywhere," he noted. "We also saw something all too rare, a true sense of national unity. Unity and resilience," he pointed out. "A capacity to recover and repair in the face of trauma. Unity in service, the 9/11 generation stepping up to serve and protect in the face of terror to get those terrorists responsible, to show everyone seeking to do harm to America that we will hunt you down and make you pay," he explained. "That will never stop, today, tomorrow, ever, from protecting America," Biden mentioned, while stressing, "Unity is what makes us who we are, America at its best.” "To me, that"s the central lesson of Sept. 11. It"s that at our most vulnerable, in the push and pull of all that makes us human, in the battle for the soul of America, unity is our greatest strength," he noted. Biden added, "We also witnessed the darker forces of human nature, fear and anger, resentment and violence against Muslim Americans, true and faithful followers of a peaceful religion. "We saw a national unity bend. We learned that unity is the one thing that must never break," he remarked. On Saturday, Biden and First Lady Jill will honor and memorialize the lives lost 20 years ago, as they will visit all three sites of the Sept. 11 attacks in New York World Trade Center, the Pentagon and a field near Shanksville, Pennsylvania. The milestone anniversary takes place just weeks after the chaotic US withdrawal from Afghanistan and the return to power of the Taliban, the faction that sheltered the terrorist group founded by Osama Bin Laden that carried out the attacks. It is also happening amid continuing concern over the COVID-19 pandemic, which has now killed more than 11 times as many people in New York City as the nearly 3,000 that perished in the 2001 attack on the World Trade Center. Former President George W. Bush, the nation"s leader on 9/11, is due at the Pennsylvania memorial and his successor, Barack Obama, at ground zero. The only other post-9/11 US president, Donald Trump, is planning to be in New York, in addition to providing commentary at a boxing match in Florida in the evening. Other observances — from a wreath-laying in Portland, Maine, to a fire engine parade in Guam — are planned across a country now full of 9/11 plaques, statues and commemorative gardens. Security was redefined, with changes to airport checkpoints, police practices and the government"s surveillance powers. In the years that followed, virtually any sizable explosion, crash or act of violence seemed to raise a dire question: “Is it terrorism?” Some ideological violence and plots did follow, though federal officials and the public have lately become increasingly concerned with threats from domestic extremists after years of focusing on international terror groups in the wake of 9/11. New York faced questions early on about whether it could ever recover from the blow to its financial hub and restore a feeling of safety among the crowds and skyscrapers. New Yorkers ultimately rebuilt a more populous and prosperous city but had to reckon with the tactics of an empowered post-9/11 police department and a widened gap between haves and have-nots. — Agencies