U.S. diplomats held a somber ceremony at the American Embassy in Kabul, Afghanistan early Wednesday, burying a piece of rubble from New York's World Trade Center under a plaque commemorating the victims of last year's terrorist attacks in the United States.

Elsewhere in Afghanistan U.S. troops came under fire at three locations, but the attacks caused no injuries or damage, as U.S.-led coalition forces continued operations against the remnants of Taleban and al-Qaida forces.

For the U.S. forces, Wednesday was a day for somber reflection, about where they were one year ago, and what they have accomplished during their tour of duty in Afghanistan.

U.S. troops at the sprawling Bagram Air Base, spent Wednesday conducting patrols, flying sorties, and carrying out routine construction duties, in the hot dusty windswept Shomali plains north of Kabul.

But unlike other days, flags flew at half-staff and there were quiet memorial services at Bagram. Everyone took a few minutes to remember where they were one year ago, when they heard the terrible news of the attacks in the United States.

Staff Sergeant Bay Boothe was at the Pentagon helping to pull the wounded and dying from the building. He says it was one of the worst days of his life - but he was reminded of his duty when he returned home to his family in Beaver Creek, Pennsylvania.

"After I came back from D.C., I walked into the house and sat down on the sofa," he said. "My daughter who was four-years-old at the time jumped up in my lap with tears in her eyes and said 'Daddy did a lot of people die.' I looked down at her and said 'yes sweetie but do not worry, Daddy is going to do everything he can to make it right and to make sure it never happens again.' "

Sergeant Boothe is an active duty reservist with the Pennsylvania Air National Guard. He arrived at Bagram on August 15, the anniversary of the day his father was killed serving in Vietnam in 1968. Sergeant Boothe served in the Gulf War, but he says the fight against terrorism in Afghanistan is different - it is far more personal.

"With Desert Shield and Desert Storm, it was the people of Kuwait who were invaded," he said. "This hit the home front - this has not happened in a long time and I do feel a sense of purpose and I do feel as an American it is my responsibility to be here. As a guardsman it gives me an extra sense of worth. When you are active duty military you serve your country -but when you are in the National Guard you can do so much more because you serve your country, your state your community and you get to directly protect your family which is why I am here."

Nearly everyone at Bagram has a story to tell about where he or she was one year ago, and how the experience then helps them today in Afghanistan. Lieutenant John Martenko was a young graduate of the U.S. Military Academy at West Point. He says the training he was receiving last September 11 helped to save his life recently, when his squad was in a firefight with Taleban and al-Qaida fighters in southeastern Afghanistan.

"I was actually in the process of training on a platoon live-fire range. I was actually role-playing the role of a platoon leader at this platoon live-fire range at the infantry officer's course in Fort Benning, Georgia," he said. "I had not even arrived at my platoon yet at the 82nd airborne division - I was still in training on September 11. The training I conducted that day on September 11 was pretty much the same exact situation I found myself in - controlling and leading those soldiers on July 27 at Ayu Khel in Paktia Province. So definitely the training paid off."

Colonel Roger King is the spokesman for the coalition forces at Bagram. He says while U.S. forces are remembering where they were one year ago, they are also aware of the changes they have helped bring about over the past year in Afghanistan. He says the Taleban and al-Qaida are largely on the run, a new national Afghan Army and police force are taking shape and a transitional government has been formed to lead Afghanistan towards democracy. Colonel King says much more needs to be done, but the progress since last September 11 has been remarkable.

"This is not a fast-food situation. You cannot drive up to the window with your dollar out and say I want it this way, and by the time you get to the second window with your dollar out you have it," he said. "It is going to take time to do it [accomplish our goals] I think you have been hard-pressed to find someone one year ago who would have given this even a remote chance of being at this stage by now."

Colonel King and other U.S. personnel say one year after the terrible terrorist attacks that killed thousands, they know the work they are doing in Afghanistan is appreciated by Americans at home.

They also say the return of more than 1.5 million Afghan refugees means their work is also valued by Afghans, who one year after September 11 have begun to reclaim their own country from terrorism.