March 10, 2023
Armed Drones: Evolution as a Counterterrorism Tool
Armed drones (also commonly called Unmanned Aerial
States. Operators can use both armed and unarmed
Vehicles, or UAVs) are unmanned aircraft designed to
drones for such a mission.
identify, surveil, and engage ground-based targets—ranging
from materiel to individuals—with kinetic weapons. The
Executing Signature Strikes: lethally targeting
United States has significantly increased its use of armed
unidentified individuals based on behaviors, patterns,
drones to attack global counterterrorism targets since the
and locations often associated with terrorist
terrorist attacks of September 11, 2001 (9/11). Prior to 9/11,
organizations.
the United States deployed unarmed drones at various
places around the world primarily to support surveillance
Targeting Equipment/Facilities: destroying buildings or
activities. Congress plays a continuing role in approving,
training areas used to house or support terrorist activity.
funding, and overseeing the use of UAVs.
Figure 1.Armed Predator Drone
Evolution of Armed Drone Usage
With the Curtiss NSC-2, the U.S. military first started using
remote-controlled aircraft in the 1930s—initially for
intelligence, surveillance, and reconnaissance (ISR)
missions, and later for deploying torpedoes and land-attack
bombs. The United States first employed drones in a
combat role in the course of the Vietnam War, including the
AQM-34 Firebee. The Firebee initially flew in the 1950s as
an aerial gunnery target drone, and then in the 1960s as an
intelligence-collection drone, and ultimately was modified
to deliver payloads in 2002. In September 2000, the United
States used an ISR drone over Afghanistan to find Osama
Bin Laden as he was being sought for his role in the 1998
terrorist attacks against the U.S. embassies in Kenya and
Tanzania. After the drone proved successful in ISR
operations—and in response to a need for additional lethal
Source: U.S. Department of Defense Photos.
tools after the attacks of 9/11—the U.S. military
increasingly outfitted drones with lethal payloads and
Possible Advantages of Using Armed Drones
deployed them to a variety of geographic locations where
Some national security professionals suggest there are
suspected terrorists resided.
many positive aspects to the use of armed drones instead of
traditional manned aircraft, including the following:
While the specific number of global armed drones being
used for counterterrorism missions is not publicly available,
Safety: unmanned drones reduce the risk that a pilot
reporting suggests that the U.S. use of armed drones has
could be killed, injured, or captured should the platform
increased in the 20 years since they were first employed.
be damaged or destroyed.
For example, from 2010 through 2020, the United States
undertook over 14,000 drone strikes in Afghanistan,
Precision: the ability of unmanned drones to get closer
Pakistan, Somalia, and Yemen. Some security observers
to ground-based targets than traditional aircraft could
have suggested that, as the United States has withdrawn
enables greater precision in targeting, thereby reducing
troops from many overseas locations and transitioned away
the risk of unintentional death and injury to
from manned counterterrorism missions, it is likely the use
noncombatants and destruction of civilian property.
of armed drones will increase.
Loitering: drones are able to linger and surveil targets
Types of Targets: Surveillance or Kinetic Strikes
for longer than manned aircraft.
Drones perform a variety of national security missions for
the United States. Specific to how armed drones support
Expense: the costs associated with acquiring,
counterterrorism missions, the following are commonly
maintaining, and operating unmanned drones are less
performed functions:
than that of manned aircrafts. In addition, the costs and
accompanying employment benefits associated with
Identifying High-Value Targets: conducting ISR to
training drone pilots are less than those for pilots of
identify terrorist leaders or those possessing special
manned aircraft.
skills deemed to be a significant threat to the United
https://crsreports.congress.gov
Armed Drones: Evolution as a Counterterrorism Tool
Possible Disadvantages of Using Armed Drones
killed civilians. Some security observers suggest that it was
Other national security professionals suggest that there
due to the increased use of this capability and targeting
could be negative aspects to using armed drones instead of
mistakes that President Obama assumed control of the
traditional manned aircraft, including the following:
decisionmaking and approval process for targeting
suspected terrorists. Under the Trump Administration, the
Normalization: Based on the aforementioned positive
use of armed drones increased across many theaters of
aspects of drones and the lower downsides of use—
operations where suspected terrorists resided with less
namely, reducing the risk of pilots being killed or
national-level oversight. President Trump delegated to field
captured—the threshold for deciding to use armed
commanders the final authority in deciding whether to
drones may lead to less rigorous policy or operational
employ this capability.
deliberations when deciding to employ this capability.
Under the Biden Administration, geographic constraints
Collateral Damage: Because drones likely offer greater
and final approval authority appear to have changed.
precision in targeting, operators may use them in
Reportedly, the Biden Administration issued rules in
situations in which a lethal strike could not—or would
October 2022 directing that armed drones be used primarily
not—be executed with manned aircraft. U.S. operators
in recognized war zones (i.e., Iraq and Syria), where field
may also use armed drones in counterterrorism
commanders will still retain delegated final authority. These
operations where there are no friendly observers on the
rules reportedly require presidential approval to add
ground to analyze potential collateral damage. This may
suspected terrorists located outside of these two countries to
result in increased collateral deaths of the civilian
a list whereby they can be targeted for lethal action,
population.
including a drone strike. Liz Sherwood-Randall, President
Biden’s Homeland Security Advisor and the person who
Counter-Productive: Noncombatants in affected
oversaw the review of the armed drone policy, stated that
countries may see widespread use of this capability
the policy is to ensure that the U.S. government is
negatively, if they view it as involving indiscriminate
“discerning and agile in protecting Americans against
killings. This dynamic could turn supportive and
evolving global terrorist challenges ... [while] minimizing
sympathetic civilians in the affected area away from
civilian casualties.”
U.S. policies and lead some individuals to be drawn to
joining terrorist groups or taking other actions counter to
Potential Questions Facing Congress
U.S. interests.
In light of the trend of increasing armed drone strikes
against counterterrorism targets, Congress may retain or
Mental Health: With many of the drone pilots being
amend the 2001 AUMF to expand or restrict the use of
located in the United States when remotely engaging
armed drones. Congress may also consider the following
suspected terrorist targets located overseas, the physical
questions in conducting oversight activities and reviewing
separation from the theater of combat and erroneous
future funding requests for the use of armed drones for
killings of civilians has led to concerns associated with
counterterrorism purposes.
post-traumatic stress disorder.
How and where are armed drones currently being used
Historical Presidential Approval Process for the
to support counterterrorism missions?
Use of Armed Drones
Since 9/11, the approval process for the use of armed
How effective has the use of armed drones been in
drones to engage counterterrorism targets overseas has
stopping terrorists from targeting United States global
evolved with each Administration. The Authorization for
security interests?
Use of Military Force (AUMF)(P.L. 107-40)—passed soon
after the terrorist attacks on 9/11—gave the President the
Does the use of armed drones allow for cost savings
ability to employ a variety of tools to track down, capture,
compared with other counterterrorism capabilities?
or kill suspected terrorists. Various Administrations have
interpreted the AUMF to (1) tighten or loosen the
Based on two decades of lessons learned regarding the
restrictions on the use of armed drones in various parts of
use of armed drones for counterterrorism missions, what
the world, and (2) retain within the Office of the President
are the advantages and disadvantages of the use of this
or delegate approval authority to field commanders for use
capability in supporting national security policies and
of this capability.
goals?
The George W. Bush Administration—soon after 9/11,
What is the current approval process for the use of
when increased funding significantly advanced armed drone
armed drones for the various types of counterterrorism-
technology—focused counterterrorism strikes mostly on the
related targets?
tribal areas of Pakistan. When the Obama Administration
came into office, the use of armed drones increased
John W. Rollins, Specialist in Terrorism and National
throughout the world, targeting suspected terrorists
Security
associated or affiliated with Al-Qaeda, ISIS, Boko Haram,
and other entities. As armed drone usage increased, so did
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the instances where U.S. drones mistakenly targeted and
https://crsreports.congress.gov
Armed Drones: Evolution as a Counterterrorism Tool
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