Jan. 9 (Bloomberg) -- The top commander of NATO said the U.S. and its allies will need to keep a large force in Afghanistan for “at least” 10 years and maintain some military presence for “decades.”

U.S. Army General Bantz Craddock said the troops will be necessary because it will be at least three years before the Afghan National Army is strong enough to maintain security in the country.

“We can’t afford to wait three years,” Craddock said in a session with reporters. “We’ve got to have a greater density of forces to be able to hold those communities, those districts, those provinces,” especially in southern Afghanistan where the Taliban insurgency is most intense, he said.

Craddock was responding to a question about a report issued yesterday by the U.S. Institute of Peace that said it would take a decade of sustained commitment for the U.S. to prevail in Afghanistan.

Asked if he agreed with that 10-year assessment, Craddock said, “At least.” Asked about the prospect of a longer time frame, he said, “Maybe not at current force levels, but I think we’ll see a presence there for decades.”

There are now about 32,000 U.S. troops and another 31,000 forces from other North Atlantic Treaty Organization members in Afghanistan. The U.S. plans to add another 20,000 to 30,000 troops over the coming year.

Attacks Surged in 2008

The level of insurgent attacks in the country rose last year to the highest level since 2001, when the U.S. invaded and ousted the Taliban from power. The Islamic militants had controlled the country and sheltered the al-Qaeda terrorist network responsible for the Sept. 11 attacks.

Craddock said he is frequently asked whether the conflict is being lost. The answer, he said, is “No, but we’re not winning fast enough.”

Craddock said the U.S. and its Afghan allies are making progress in the eastern part of the country, where a program of building roads, schools and markets is helping marginalize the insurgents.

In the south, in contrast, there are too few troops to protect the population and provide security for reconstruction projects, he said.

Craddock said he believes the amount that insurgents are receiving from illicit drug trafficking has doubled in the past year to about $200 million annually. That makes an anti-narcotics program essential to quelling the Taliban, he said.

To contact the reporter on this story: Ken Fireman in Washington at kfireman1@bloomberg.net

Last Updated: January 9, 2009 11:52 EST