KABUL, AFGHANISTAN - DECEMBER 14: U.S. Joint Chiefs of Staff Chairman Adm. Michael Mullen holds a press conference December 14, 2009 in Kabul, Afghanistan. Adm. Mullen, America's highest ranking military officer, expressed concern about the 'growing level of collusion' between Taliban insurgents in Afghanistan and al-Qaida and other militants in Pakistan. (Photo by Majid Saeedi/Getty Images)