"This is my third trip, and I do think every time Afghanistan looks better," Bush told the troops.
She said she visited women training to be police and other studying the Afghan constitution.
"(One) woman told me that she was the first female police officer, and because she was inspired by her governor, Governor Habiba Sarabi, the first female governor in Afghanistan," Bush said.
Watching women studying the constitution reminded her of how far the country's advanced since the Taliban's reign "when women were not even allowed in school and there was no democratic constitution to be studied," she said.
She said she also attended a ribbon-cutting ceremony for the construction of a new road in Bamiyan that is underwritten by the United States.
"But I want you to know that I know that all of these encouraging stories and all of these terrific things that I saw today have been made possible by your efforts and the efforts of the United States military," Bush said.