Gordon D. Johndroe, a spokesman for the National Security Council, said the interagency review covered anti-Taliban and counternarcotics activities as well as efforts to counter extremism and to integrate the central government with local and provincial governments.

“We are proud of the progress that has been made in the last five years, but know there is more to do,” he said. “The United States is committed to the people of Afghanistan for the long term.”

Mr. Neumann, who has been the ambassador here for just over a year, laid out a full menu of tasks that he said the American-led effort needed to accomplish in Afghanistan, including reviving the country’s economy, building roads and power plants and improving security. He said plans drafted in 2002 to train the army and police force needed to be revamped and expanded.

Mr. Neumann, a decorated Vietnam veteran whose father served as the American ambassador to Afghanistan from 1966 to 1973, said the country’s security forces had to be better supplied. “We have a war, not in all parts of the country, but we have a war,” he said. “So we have to build a much better equipped army and a much better-equipped police.”

Training the police represents an even larger challenge than strengthening the army, Mr. Neumann said. “The police need a whole huge, major effort,” he said. “That wasn’t what the program was designed to do when we were at peace.”

The senior American official said Afghans widely saw the force as corrupt and failing to provide security.

A sharp increase in suicide attacks and roadside bombings over the past two years has persuaded many Afghans that security has sharply deteriorated under Mr. Karzai. The tactics appear to have migrated from Iraq, according to the official, probably via the Internet and people traveling between the countries.