Wolf also is worried by the persistent problem of Taliban havens on the Pakistan side of the border.
Navy Adm. James Stavridis, the top NATO commander, said he sees no need to change course in Afghanistan.
"As I look at the broad sweep of our strategy there, I am convinced that we should continue with transitioning Afghanistan's security to the Afghans," he told a Senate panel Thursday. He called himself "cautiously optimistic" that the plan now in place ultimately will succeed in stabilizing the country.
In a separate appearance before Congress, Gen. Ray Odierno, the Army chief of staff and former top U.S. commander in Iraq, framed the problem diplomatically by saying only a tiny fraction of Afghan security forces are targeting Americans. He applauded U.S. troops for their restraint in the face of treachery.
"I know it's very difficult for (U.S. soldiers) when we have somebody who is working hard, dedicating themselves to the mission in Afghanistan and somebody who they're helping comes behind and kills them," he said.
Robert Burns can be followed on Twitter at http://www.twitter.com/robertburnsAP
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