This morning in Afghanistan, thousands of American warriors woke up in the country where 9/11 was planned. Some were just toddlers on September 11, 2001.

Today marks the 17th anniversary of the worst terrorist attack in American history. While the horrors of that day drift in and out of our national consciousness, the sacrifices it spawned never stopped.

It started with heroes like U.S. Army veteran Rick Rescorla, who was in the World Trade Center’s South Tower when its twin was struck by the first hijacked plane. Ignoring initial speculation that the crash was an accident, Rescorla – a security official for Morgan Stanley – ordered all 2,700 employees out.

“He wasn’t thinking about himself after that first plane hit,” Rick’s wife, Susan, told me in 2011.  “He did what he did in Vietnam: leave no man behind.”

After calmly leading almost every Morgan Stanley employee out of the South Tower, even as it was struck by the second hijacked jet, Rescorla ran back inside to save more lives. He was last seen heading upstairs just before the building collapsed.

Along with the first responders who ran inside the burning World Trade Center and Pentagon, as well as the citizens who charged the hijackers of United Flight 93, Rescorla was one of the first heroes of our country’s long war on terrorism. Yet when I spoke to Rick’s widow, she was equally focused on spotlighting the ongoing burdens being shouldered by America’s military.

“I never look at Ground Zero as a killing field,” Susan said.  “It’s a place where our country went to war.”

The 9/11 “Tribute in Light” as seen from New Jersey’s Liberty State Park on September 11, 2006, the five year anniversary of the 9/11 attacks.

Indeed, the constant struggle that began 17 years ago continues at this very moment. As of this writing, the loved ones of U.S. Army Command Sgt. Maj. Timothy Bolyard, who made the ultimate sacrifice in Afghanistan earlier this month, are preparing to lay the fallen soldier to rest.

Command Sgt. Maj. Bolyard had been serving in the military for seven years when our country was attacked and would spend the next 17 deploying to more of the world’s most dangerous places. When Bolyard was shot and killed on September 3, he tragically became one of almost 7,000 U.S. troops to lose their lives on America’s post-9/11 battlefields.

As the The Stream‘s daily and weekly military features remind us, our valiant men and women in uniform work tirelessly to keep us safe. From deployed service members and their loved ones to wounded veterans and Gold Star families, our nation’s military community is a giant chest of national treasures.

First and foremost, each 9/11 anniversary is a day to honor the attack’s 2,753 victims and their families. It is also a powerful reminder that for all that divides us, we are still surrounded by heroes willing to lay down their lives in defense of liberty.

September 11, 2001, was one of the worst days in our country’s history. It was also the moment when a new generation stepped forward to defend freedom. As President George W. Bush said after the attacks, “the course of this conflict is not known, yet its outcome is certain. Freedom and fear, justice and cruelty, have always been at war, and we know that God is not neutral between them.”

Some of our nation’s defenders are unable to recall the harrowing images of victims falling from the Twin Towers, stretchers being carried from the Pentagon or smoke rising from a silent Pennsylvania field. Still, just like Rick Rescorla and Command Sgt. Maj. Timothy Bolyard, these young patriots are willing to sacrifice everything.

Their courage is America’s greatest blessing.

Tom Sileo is a contributing senior editor of The Stream. He is co-author of three books about military heroes: 8 Seconds of Courage, Brothers Forever and Fire in My Eyes. Follow Tom on Twitter @TSileo.