A new book details how US counterterrorism efforts evolved in the 10 years after 9/11 from a kill-and-capture strategy to one of Cold War deterrence.
A new study estimates the wars in Afghanistan and Iraq have cost the U.S. between $2.3 to $2.6 trillion.
Afghan insurgents shot down the US transport helicopter in the Tangi Valley of Wardak Province, to the west of Kabul.
NATO troops hand power over to the Afghan National Army in Lashkar Gar, the capital of Helmand province in southern Afghanistan.
A suicide bomb attack killed at least four people at the funeral of Ahmed Wali Karzai in Kandahar.
A six-hour attack by suicide bombers at Kabul's Intercontinental Hotel left at least 21 people dead.
President Obama will announce his exit strategy from what is now America's longest war, Afghanistan. The fighting, however, is likely to continue for a long time.
Hamid Karzai, the President of Afghanistan, has stepped up warnings to NATO, saying it risks becoming an "occupying force."
Now that Osama Bin Laden has been killed, experts consider how US strategy in the war in Afghanistan will change.
The war in Afghanistan has displaced thousands of people from their homes, adding to the 43 million refugees around the world.