FILE - In this Dec. 28, 2011 file photo, a former Taliban fighter places a range of bullets before surrendering it to Afghan authorities, as part of a peace-reconciliation program in Herat, west of Kabul, Afghanistan. The Islamic State group controls a third of both Syria and Iraq, where it declared a caliphate governed by an extremely harsh interpretation of Shariah law and demanded the allegiance of the world’s Muslims. The Taliban, by contrast, are narrowly focused on Afghanistan and Pakistan, and some leaders have even responded to past peace overtures. (AP Photo/Reza Shirmohammadi, File)
From Afghanistan and borderlands of Pakistan to Iraq and North Africa, radical Islamists eager to spread their strict interpretation of the Muslim faith and topple Western values have bombed, beheaded and slaughtered — undermining the White House narrative and raising questions about its strategy. (Associated Press)
Afghan President Ashraf Ghani, left, former President Hamid Karzai, center, and Chief Executive Abdullah Abdullah, right, attend a ceremony marking the completion of security transition to Afghan security forces in Kabul, Thursday, Jan. 1, 2015. Afghan police are investigating a rocket strike on a wedding party that killed at least 28 people, many of them women and children, an official said Thursday, as President Ashraf Ghani marked the country’s transition to full sovereignty after the 13-year international military mission to rid Afghanistan of insurgents officially ended. (AP Photo/Rahmat Gul)
FILE PHOTO - Rangers from Headquarters and Headquarters Company, 3rd Battalion, 75th Ranger Regiment and a multi-purpose canine pause during a nighttime combat mission in Afghanistan. Courtesy U.S. Army.
FILE PHOTO - Soldiers from Company H (Hawk Co.), 3rd Squadron, 2nd Striker Cavalry Regiment, dismount from a their vehicle and prepare to raid a series of compounds Nov. 22, in the Maywand District, Afghanistan
Chris Marvin (left) was an Army helicopter pilot before suffering numerous injuries in a 2004 crash on the Afghanistan-Pakistan border. Never one to go down without a fight, Mr. Marvin spent years recuperating and became managing director of Got Your 6, a nonprofit that works to inspire and assist other combat veterans like himself.
Sgt. Bowe Bergdahl is awaiting an Army decision on whether he will face criminal charges for walking off his base in Afghanistan on June 30, 2009, and becoming an enemy captive until last May. (Associated Press) ** FILE **
The A-10 Warthog has the capability to fly low enough so its crew can detect friendly forces on the ground, preventing tragedies like the one in June when a B-1B dropped a 500-pound bomb onto U.S. soldiers protecting a helicopter landing zone in Afghanistan. (Associated Press)
FILE - In this Oct. 28, 2009 file photo taken with a night vision scope, U.S. Special Operations forces search a home during a joint operation with Afghan National Army soldiers targeting insurgents operating in Afghanistan's Farah province. Afghan President Ashraf Ghani has ordered a top-to-bottom review of the practices of the country’s defense forces, including discussing a possible resumption of controversial night raids banned by his predecessor, the Associated Press has learned. The move appears aimed at revamping the military for the fight against the Taliban amid new indications that U.S. and international forces will play a greater role than initially envisaged. (AP Photo/Maya Alleruzzo, File)
U.S. Special Operations forces engage in a joint operation with Afghan National Army soldiers targeting insurgents operating in Afghanistan's Farah province, Oct. 29, 2009. (Associated Press) ** FILE **
U.S. Central Commander Gen. David Petraeus looks on at right as Defense Undersecretary Michele Flournoy testifies on Capitol Hill in Washington, Wednesday, June 16, 2010, before the Senate Armed Services Committee hearing on Afghanistan. (AP Photo/Drew Angerer)
Defense Undersecretary for Policy Michele Flournoy, left, talks with Marines Lt. Gen. John Paxton, director for operations, the Joint Staff, talk on Capitol Hill in Washington, Monday, Feb. 22, 2010, prior to their testifying before the Senate Armed Services Committee hearing on Afghanistan. (AP Photo/Manuel Balce Ceneta)
U.S. Army Spc. David Walls, of Warren, Mich., Mine Detection Dog Handler, 49th Engineer Detachment, oversees Sergeant Homer, a mine detection dog, as he performs a mine-proofing sweep at the Russian Grain Silo Combat Outpost, Kandahar, Afghanistan. The COP is the intended site of a 10 mega-watt power plant that will provide electricity to the western side of Kandahar. Walls and Homer are deployed to Kandahar Air Field, Afghanistan. (ISAF photo by TSgt Samuel Padilla/released)