Kimberly Kagan is president of the Institute for the Study of War. Frederick Kagan is director of the Critical Threats Project and a scholar at the American Enterprise Institute.
Will the United States continue to conduct counterterrorism operations in South Asia? That question is central to any discussion about U.S. troop presence and mission in Afghanistan. The answer can be yes only if we pursue and support the current strategy, retaining roughly 68,000 troops in Afghanistan into 2014 and about half that number thereafter.
Amateurs can discuss imaginary, over-the-horizon “light footprint” strategies. Professionals must consider logistics. Physics and military reality dictate the minimum number of troops needed to have any U.S. presence in Afghanistan without inviting calamities worse than the events in Benghazi, Libya. The presence of U.S. forces in Afghanistan alone permits counterterrorism operations in Pakistan. It’s this simple: Either we keep the necessary number of troops in Afghanistan or operations against al-Qaeda and its affiliates in Afghanistan and Pakistan cease.
The principal terrorist concentrations in South Asia are in Pakistan’s federally administered tribal areas. Al-Qaeda and affiliated groups have sought safety in Afghanistan primarily in Konar and Nuristan provinces. U.S. forces could target terrorists without maintaining a ground presence in three ways: using armed Predator drones, special mission units or precision-guided munitions dropped from manned aircraft. Without bases in Afghanistan, the tyranny of distance rules out the first two options; the requirement for accuracy and certainty rules out the last.
North Waziristan is more than 600 miles from the nearest coastline; the other sanctuaries are farther. The U.S. Air Force reports that armed Predator drones have a range of about 1,150 miles — not enough to get to Waziristan and back again from the coast, much less to orbit and observe a target. Special mission units would have to parachute from transport aircraft because no helicopter in the U.S. inventory can fly that far. But they could not return because aircraft cannot land in the mountains of Eastern Afghanistan or in Pakistan. Manned aircraft can drop precision weapons on targets in Afghanistan, but they fly too fast to loiter over potential targets. Their bombs hit precisely what they are aimed at, but fast-moving aircraft cannot ensure that the target was actually there. There is no over-the-horizon solution to targeting terrorists in South Asia.
Bases in Afghanistan obviate all these problems. U.S. forces operating from Khost, Jalalabad and Kandahar can strike targets in Afghanistan (or Pakistan) with Predators and special mission units. Such operations have been critical to the success of counterterrorism operations in this region, including the killing of Osama bin Laden (Abbottabad is about 150 miles east of Jalalabad, 750 miles from the Indian Ocean).
The minimum U.S. footprint to sustain counterterrorism operations requires bases near Jalalabad, Khost and Kandahar to reach known terrorist havens (Khost and Jalalabad are less than 100 miles apart but are separated by a 10,000-foot mountain range). Each base requires an airstrip to fly Predators and move supplies by air. Each must also have aircraft ground crews and support the special mission units.