GRAFENWOEHR, Germany -- For Staff Sgt. David Sanders, Headquarters and Headquarters Company, 172nd Infantry Brigade, the recruiter's call came at "the perfect time."

Just weeks previous, the attack on the Twin Towers on Sept. 11, 2001, had left Sanders enraged and itching for a way to help his traumatized nation.

"The only thing that went through my mind was, 'Oh hell no! Not my country. You did not just do this to my country,'" he said.

So when the recruiter rang, Sanders enlisted.

Tuesday marked the 11th anniversary of 9/11, the catalyst that altered the nation's sense of security. In the patriotic fervor that overtook the U.S. in the post-9/11 months and years, men and women flocked to recruiting stations or answered a recruiter's entreaty with an energetic "yes."

Though this post-9/11 demographic is shrinking, many in their ranks have remained, turning a patriotic impulse into a lifetime of service. Furthermore, newer Soldiers, fundamentally affected by the attacks, still cite 9/11 as the driving force behind their military service.

Lt. Col. Michael Stanley, regimental surgeon, Regiment Headquarters and Headquarters Troop, 2nd Cavalry Regiment, was working as a doctor in Brooklyn when the planes hit the Twin Towers. Stepping off the subway that morning, the smoldering buildings were the first things he saw.

That moment, recalled Stanley, transformed his physical horizons -- the Manhattan skyline -- and his emotional horizons.

"Emotionally, I mean, we were attacked. I was angry and frustrated and the thought that burned through my mind was, 'How could I ever prepare for something like this?'"

His answer was to join the Army. Stanley contacted a recruiting agent in October 2001, and in July 2002, he was a Soldier.

"It seemed like the right thing to do to offer my skills to the military, and for that I have no regrets," said Stanley. "It's an honor for me to take care of Soldiers and their families and make sure they're ready to defend their nation."

Sanders, who felt a similar call to defend in the immediate shock of 9/11, said that his anger over the attacks, not his sense of purpose, has softened over time.

"I stayed in. I re-enlisted because I wanted to serve my country. I wanted to protect my country and its people," said Sanders, adding, "I'm going to be doing this until I retire. I'm going to be fighting terrorism. I live to serve and this is how I choose to serve. I put on this uniform."

After nearly 11 years embroiled in war and an economic downswing in the U.S., patriotic fervor has been upstaged by the Army's more tangible benefits. But, young initiates moved by the attacks as children and teenagers are still joining the Army with 9/11 as their driving force.

Spc. Carlos Alvarez, Regiment Headquarters and Headquarters Troop, 2nd Cavalry Regiment, joined in 2009, directly out of high school. A native of the Bronx, the attacks in 2001 touched him personally. Caught up in the confusion of the day, Alvarez feared his brother had been trapped in the middle of the destruction. He later discovered that numerous friends lost parents in the Towers.

It was then, at age 12, that Alvarez informed his parents of his intention to join the Army.

"It was the fact that I felt so helpless when things like that happen," he said. "It was reassurance that things could get a little better. Maybe I could change something, you know."

Alvarez says he's found his niche in the Army and has learned from his time in service. His deployment in 2010 to Afghanistan opened his eyes to the strife of local civilians.

"Not everybody is guilty down there. Some need the help. Some want the help because they can't get it because of where they are," Alvarez said. "They want to progress."

Spc. Lloyd Gookins, Regiment Headquarters and Headquarters Troop, 2nd Cavalry Regiment, saw his thought process follow a similar path. Emotionally jostled by the attacks on 9/11 when he was only 10 years old, Gookins began talking to an Army recruiter at 15, determined to have a future in the military.

"I feared for further attacks," explained Gookins. "The impact it had on me as a young child enticed me to join the military and ensure these things don't happen anymore. I wanted to fight the war on terrorism."

After a deployment in Iraq, Gookins explains he "became much more knowledgeable."

"I became much more culturally aware and realized that people wanted us there and that's something you can't experience without going there. It made me much more open-minded."
As for 9/11 and the reason he became a Soldier, Gookins says it's not really a topic of discussion among his comrades in arms.

"People don't really talk about why they joined," said Gookins. "We're fixated on the fact that we work with each other. Why we joined doesn't matter. What we do matters."