 
 
 
 INSIGHTi  
The Afghanistan Withdrawal: Military and 
Defense Implications 
August 17, 2021 
After a rapid Taliban campaign to capture cities and territories formerly controlled by the Government of 
the Islamic Republic of Afghanistan (GIRoA), on August 15, 2021, the Taliban took Kabul and the 
President of GIRoA, Ashraf Ghani, fled the country.  
Information regarding the situation on the ground in Afghanistan and U.S. troop numbers is fluid and 
should be treated with caution. This Insight, which may be updated as circumstances warrant, is intended 
to assist Congress as it considers the military and defense implications of the withdrawal while events 
unfold.   
Current Military Footprint and Mission 
Operation Al ies  Refuge (OAR) was initiated on July 17, 2021, to support relocation flights for Afghan 
nationals and their families eligible  for Special Immigrant Visas (SIVs). On August 12, 2021, in light of 
the deteriorating security situation in Afghanistan, Secretary of Defense Lloyd Austin and Secretary of 
State Antony Blinke
n  informed Ghani the United States would begin reducing its civilian  footprint in 
Kabul, and would accelerate Special Immigration Visa (SIV) flights previously undertaken as part of 
OAR. The rapid collapse of GIRoA and subsequent Taliban takeover of Kabul has, to many observers, 
underscored that plans to evacuate U.S. personnel and Afghan partners needed to be accelerated.  
In support of OAR and U.S. withdrawal operations, the Department of Defense
 (DOD) has announced 
that at least the following actions wil , or have been, taken: 
  Three infantry battalions—two Marine Corps, one U.S. Army—would deploy to Hamid 
Karzai International Airport.  
  
A joint U.S. Army/Air Force support element of around 1,000 personnel would be sent to 
Qatar, and possibly to Afghanistan (or to other areas where the Afghans wil  be 
processed), to facilitate the processing of SIV applicants. 
  Two battalions of the 82nd Airborne Division would be deployed to Afghanistan. It was 
previously announced that one of these battalions would be sent t
o Kuwait as a quick 
reaction force
. The deployment of a second battalion was announced on August 16, 2021. 
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https://crsreports.congress.gov 
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DOD officials have further noted: 
  As of August 17, 2021
, approximately 4,000 troops had arrived in Kabul as part of the 
surge of support for OAR and withdrawal operations. 
  Betwee
n 650 a
nd 1,000 U.S. troops were already on the ground conducting withdrawal 
operations. 
  As in al  cases, U.S. service members have the right to self-defense if attacked.  
  DOD stil  plans to complete the ongoing troop drawdown in Afghanistan by the end of 
August 2021. 
Questions and Considerations 
The rapid collapse of the Afghan National Defense and Security Force (ANDSF), as wel  as GIRoA itself, 
has
 chal enged some of the central premises of post-September 11, 2001, national security policies and 
raised questions about local and regional Afghan security dynamics that are currently being debated by 
scholars and practitioners and that Congress may explore in its own deliberations. These include the 
following: 
What were U.S. military options? 
The Trump Administration concluded a withdrawal deal with the Taliban in February 2020, stipulating 
that U.S. forces would withdraw from Afghanistan by May 31, 2021, in return for some counterterrorism 
assurances from the Taliban. The Biden Administration chose to delay the withdrawal date to August 31, 
2021. Some observers contend that the Biden Administrati
on  could have chosen to ignore the agreement 
and retained a smal  footprint in the country comprising several thousand troops in order to facilitate a 
better peace agreement. According to this view, the costs of retaining such a force would have been 
minimal compared with the security risks associated with Afghanistan’s collapse. By contrast, President 
Biden contend
ed that retaining such a presence would have been unfeasible; the smal  number of troops 
would not have been sufficient to deter Taliban forces and 
a reescalation of forces and capabilities in 
Afghanistan would ultimately have been required. Stil  others contend that even assuming a minimal 
footprint could have been feasible, doing so was not wort
h risking further U.S. resources and lives. 
What might this mean for security cooperation efforts? 
A central aspect of the U.S. and coalition campaign in Afghanistan was training and equipping a 
sustainable ANDSF. Yet some observers, looking t
o long-standing deficiencies in some components of the 
ANDSF, might
 question the efficacy of U.S. efforts t
o build the security capacity of al ies and partners writ large. According to this logic, recent events in Afghanistan could suggest to some that such capacity-
building efforts are strategical y problematic and that the U.S. should exercise caution when trying to 
build foreign militaries. Others might counter that the situation in Afghanistan was unique
, particularly as 
such efforts were being conducted during wartime, and that there wer
e myriad other factors leading to the 
collapse—including the withdrawal of U.S. support—that are not always present in other security 
cooperation endeavors.  
What was the U.S. exit strategy? 
There are at least two separate but related aspects to questions regarding the U.S. exit strategy. At a 
strategic level, some observers contend that the col apse of GIRoA and the ANDSF wa
s ultimately 
inevitable, given that over time t
he U.S. had built an Afghan security apparatus 
  
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largely dependent upon U.S. forces and capabilities, and overseen 
by unitary political  structures that were 
inappropriate in an Afghan context alongsi
de endemic corruption. Others contend that the U.S. never fully 
factored effective war termination into its Afghanistan campaign strategies and force designs, resulting in 
a military effort that did not enable a satisfactory conclusion to the war. At an operational level, some 
observer
s question the robustness of the plan to withdraw U.S. troops and key Afghan partners from 
Afghanistan. Congress may scrutinize whether, and how, military campaign planning could have 
containe
d these significant strategic and operational flaws. 
What new threats might emerge as a result of this withdrawal?  
The initial  purpose of the war in Afghanistan after September 11, 2001, was ostensibly to depose the 
Taliban and ensure that Al Qaeda could never again mount an attack against the United States or its al ies.  
Almost 20 years later, t
he Taliban control more of Afghanistan than they did prior to the U.S. 
intervention. Some express concern tha
t U.S.-provided ANDSF equipment has fal en into Taliban hands 
and that thousands of Afghan government prisoners—some of whom may be affiliated with Al Qaeda and 
the Islamic State
—have been released. Some observers may also question the extent to which the 
Taliban’s victory might energize jihadist movements in other theaters.  
 
Author Information 
 Kathleen J. McInnis 
  Andrew Feickert 
Specialist in International Security 
Specialist in Military Ground Forces 
 
 
 
 
 
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