Over the past five years, the focus of U.S. counterterrorism strategists has remained on the Middle East, especially after the emergence of ISIS in 2014, while Islamist terrorist organizations operating in South Asia have been considered a secondary threat. However, the fact remains that South Asia is home to more Islamist terrorist organizations than any other region of the world. Al-Qaeda was born there, in Afghanistan, and ISIS has roots in the region. But at the turn of the decade both global jihadist groups are now facing major challenges and the critical question is whether they will manage to survive this period of crisis amid a severe leadership vacuum following the death of ISIS’s supreme leader and caliph, Abu Bakr al-Baghdadi, and the killing of al-Qaeda heir apparent Hamza bin Laden.