More details are emerging, although, according to the New York Times, there aren't any reporters traveling wih Obama to Afghanistan:
Mr. Obama touched down in Kabul about 11:45 a.m., according to a pool report released by his aides. In addition to attending briefings with military leaders, he hoped to meet with President Hamid Karzai of Afghanistan before flying to Iraq later in the weekend.
His trip was cloaked in secrecy, which advisers said was due to security concerns set forth by the Secret Service. His whereabouts have been unknown since he departed Chicago. He left Andrews Air Force Base near Washington on Thursday afternoon, according to a pool report, and turned up in Afghanistan on Saturday.
Before he left the United States, he gave a brief outline of his trip to two pool reporters traveling with him from Chicago to Washington. No reporters accompanied him to Afghanistan.
“Well, you know, I’m more interested in listening than doing a lot of talking,” Mr. Obama said. “And I think it is very important to recognize that I’m going over there as a U.S. senator. We have one president at a time, so it’s the president’s job to deliver those messages.”
Mr. Obama’s arrival opened a weeklong foreign trip that includes visits to Iraq and two other stops in the Middle East as well as appearances in three European capitals. His tour of Afghanistan and Iraq are part of a Congressional delegation — similar to trips that Senator John McCain, the presumptive Republican nominee, made in the spring — in which he is joined by Senators Chuck Hagel, Republican of Nebraska, and Jack Reed, Democrat of Rhode Island, both of whom have been mentioned as possible vice presidential running mates.




