Bidens, Obamas & Clintons Commemorate 9/11 in NYC, Plus: Celebs Remember the Day

President Joe Biden and First Lady Jill Biden led a delegation of dignitaries and famous faces gathered in Lower Manhattan Saturday morning to commemorate the 20th anniversary of the 9/11 attacks.

As seen in the photos above, former President Bill Clinton, Hillary Clinton, former President Barack Obama, Michelle Obama, President Biden, Jill Biden, former NYC Mayor Mike Bloomberg and his partner Diana Taylor, Speaker of the House Nancy Pelosi, Senate Majority Leader Chuck Schumer and Sen. Kirsten Gillibrand were front and center at the solemn annual ceremony, which included six separate moments of silence to honor when each tower of the World Trade Center was struck, when they each fell, and the times corresponding to the attack on the Pentagon and the crash of Flight 93, which spared the U.S. Capitol.

Bruce Springsteen performed "I'll See You in My Dreams" after one of the moments of silence, and Broadway star Kelli O'Hara sang "You'll Never Walk Alone."

Others on hand included NYC Mayor Bill de Blasio and former NYC Mayor Rudy Giuliani. Vice President Kamala Harris and former President George W. Bush spoke at a ceremony at the Flight 93 National Memorial in Shanksville, Pennsylvania, with Harris calling for "a united America" and Bush condemning extremists abroad "and at home," saying they are "children of the same foul spirit."

President Biden's social media bore a moving collage of images showing the faces of some of the people lost on 9/11, along with the simple message, "We will never forget."

Former President Obama wrote on Instagram, "Today we honor the nearly 3,000 men, women, and children who died on September 11, 2001, and even more who lost their lives in service to our country in the two decades since. We reaffirm our commitment to keep a sacred trust with their families — including the children who lost parents, and who have demonstrated such extraordinary resilience. But this anniversary is also about reflecting on what we’ve learned in the 20 years since that awful morning. That list of lessons is long and growing. But one thing that became clear on 9/11 — and has been clear ever since — is that America has always been home to heroes who run towards danger in order to do what is right."

He went on, "For Michelle and me, the enduring image of that day is not simply falling towers or smoldering wreckage. It’s the firefighters running up the stairs as others were running down. The passengers deciding to storm a cockpit, knowing it could be their final act. The volunteers showing up at recruiters’ offices across the country in the days that followed, willing to put their lives on the line. Over the last 20 years, we’ve seen the same courage and selflessness on display again and again. We saw it a decade ago when, after years of persistence, our military brought justice to Osama bin Laden. And we’re seeing it today — in the doctors and nurses, bone tired, doing what they can to save lives; the servicemembers, some of whom weren’t even born 20 years ago, putting themselves at risk to save Americans and help refugees find a better life; the first responders battling roaring fires and rising waters to bring families to safety. They represent what is best in America, and what can and should bring us together."

Obama concluded, "9/11 reminded us how so many Americans give of themselves in extraordinary ways — not just in moments of great crisis, but every single day. Let’s never forget that, and let’s never take them for granted. #NeverForget911."

In a taped address, President Biden said Friday that the take-away from 9/11 was the "true sense of national unity" that emerged in the weeks following the attacks, and the "heroism everywhere."

In a time when the U.S. seems more divided than at any time since the Civil War, Biden went on to urge Americans to recall that, "Unity is our greatest strength."

Many celebrities took to social media to commemorate 9/11, some remembering where they were on the day.

Queen Elizabeth, in a message to President Biden, said, "As we mark the 20th anniversary of the terrible attacks on September 11 2001, my thoughts and prayers, and those of my family and the entire nation, remain with the victims, survivors and families affected, as well as the first responders and rescue workers called to duty. My visit to the site of the World Trade Center in 2010 is held fast in my memory. It reminds me that as we honour those from many nations, faiths and backgrounds who lost their lives, we also pay tribute to the resilience and determination of the communities who joined together to rebuild."

New Yorker Mariah Carey tweeted, "On this anniversary of 9/11, I find myself remembering the shock and anguish we all experienced with painfully deep sadness. Vivid images of the skyline I grew up loving so much, suddenly changed forever."

Prince Harry and Meghan Markle devoted the homepage of their charitable Archewell site to a list of all the names of the victims of 9/11.

Hillary Clinton, a New York senator at the time of the 9/11 attacks, posted an image of herself and current Senate Majority Leader Chuck Schumer at a past 9/11 memorial, writing, "Twenty years on. We will never forget.⁣"

Kris Jenner posted a mosaic of the dead from 9/11 on Instagram, writing, "20 years ago today. Take a moment this morning to remember and honor those who lost their lives, the families and friends who lost their loved ones, and the survivors of the horrific attacks on 9/11. We’ll never forget the sacrifices made by the firefighters, early responders and civilians who risked everything to help others in the most incredible and unforgettable display of heroism. I’ll never forget that day, and my thoughts are with everyone who lost someone they love. Life is so precious and today is a reminder to me to cherish every single moment I have with those I love. We must show each other love, forgiveness, grace, and be thankful for the time we have together. #NeverForget #911."

Viola Davis Instagrammed a stark image of the NYC skyline with the words "Never forget." emblazoned across it, writing, "Will never forget this day. Will never forget the lives lost. Sending love and prayers to the familes, loved ones of the fallen.💔❤🙏🏿 Today marks 20 years since the attacks on September 11, 2001. The lives lost 20 years ago can never be replaced; the pain can never be forgotten. Please take a moment today to hold those taken and their loved ones in your thoughts."

Kelsey Grammer recalled the death of "Frasier" co-creator David Angell and his wife on one of the hijacked flights, telling Deadline, "I was awakened by a friend of mine who lives in New York. He said, ‘They got us, they got us, they’ve taken out the World Trade towers.’ I turned on the TV and saw what was going on. I remember I’d invited David and his wife to come to a party that weekend; I spoke to him on Saturday. He said, ‘Oh, we were going to come home but we decided we’d stay an extra couple of days. We’re going to come back on Tuesday.’" Grammer also recalled pulling strings to get to Ground Zero, where he said he witnessed bodies being recovered. "A nurse came out and said, ‘Will you guys go visit the morgue? There’s no good news here. It might make people feel good to see you there.’ We did that and said hello to the doctors and thanked them. It was a pretty difficult time, but I was glad I went. It was just part of our mourning.”

Mark Wahlberg tweeted, "We will #NeverForget."