Jill Biden Remembers the Moment That 'Changed Us All in Some Way' on 20th Anniversary of 9/11

First Lady Jill Biden is remembering one of the most pivotal moments in United States history on the 20th anniversary of 9/11.

In an exclusive statement, Dr. Biden, 70, shares, "At 8:46 AM ET, on September 11, 2001, our memories split into 'before' and 'after.' That moment changed us all in some way."

"Twenty years ago today, in our shared experience of shock, grief, and resolve, we found unity. We leaned on each other, realizing we are stronger together than apart," she says.

Continues Dr. Biden, "It can be difficult to untangle meaning from loss and tragedy, when nothing seems clear and we just want one more minute of the 'before' again. Our feelings never follow a straight line. Yet, as we remember those we lost because of the September 11th attacks, and contemplate our changed world since, may we honor their lives and legacies by reaching out for each other again in unity, recognizing that our similarities are infinite and our differences precious."

Jeff Fusco/Getty

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For Dr. Biden, September 11, 2001, began with a morning run. The day was quiet, as her husband Joe Biden — then a senator of Delaware — was commuting to Washington, D.C., and their daughter Ashley was away at college.

She was preparing to teach an English class at Delaware Technical Community College when she first saw news coverage that a plane had crashed into the North Tower of the World Trade Center.

Dr. Biden then immediately called her husband, who was not aware of what was taking place in New York City at the time as he was on an Amtrak train, according to the Associated Press.

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"Oh my God. Oh my God. Oh my God," Dr. Biden reportedly cried on the phone as the second tower was hit.

Shaken from what she had just witnessed, Dr. Biden went to work — only to find students and faculty members in the same distressed state. When Dr. Biden ended her class and drove to check on her younger sister Bonnie — who was a flight attendant at the time and knew several of the crew members who worked on the United flight that crashed in Shanksville, Pennsylvania — she was greeted by an equally emotional sibling.

SUSAN WALSH/POOL/AFP via Getty Dr. Jill Biden

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In a six-minute video released on Friday, President Biden, now 78, reflected on the thousands of lives that were taken two decades ago, saying, "To the families of the 2,977 people from more than 90 nations killed on September 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."

"We honor all those who risked and gave their lives in the minutes, hours, months, and years afterward," President Biden said in the pre-recorded address. "The firefighters, the police officers, EMTs and construction workers, and doctors and nurses, faith leaders, service members, veterans, and all of the everyday people who gave their all to rescue, recover, and rebuild.

"But it's so hard, whether it's the first year or the 20th," continued President Biden. "Children have grown up without parents, and parents have suffered without children. Husbands and wives have had to find ways forward without their partners in their life with them."

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"No matter how much time has passed, these commemorations bring everything painfully back as if you just got the news a few days ago," he added. "So on this day, Jill and I hold you close in our hearts and send you our love."

In his address, President Biden also commemorated the heroism and "true sense of national unity" shown in the days following 9/11.

"We saw national unity bend. We learned that the unity is the one thing that must never break," President Biden noted. "Unity is what makes us who we are, America at its best. To me, that's the central lesson of September 11th. It's that at our most vulnerable, in the push and pull of all that makes us human, in the battle of the soul of America, unity is our greatest strength."