Anthony H. Cordesman of the Center for Strategic and International Studies told the New York Times some of the corruption will fade as the United States and its allies cut back aid to Afghanistan.
"It's a little late in the game to worry about anti-corruption measures because what in the world is the alternative going to be?" Cordesman said. "If you find people who aren't corrupt, it is largely because they haven't had the opportunity."
One of the most public corruption scandals involved the near collapse of Afghanistan's Kabul Bank.
U.S. officials say they have few expectations that the former bank chairman will be prosecuted by President Hamid Karzai's government.
In December, Karzai was told that investigators found the Afghan Army's former surgeon general stole tens of millions of dollars worth of drugs from the country's main military hospital financed by the United States.