https://crsreports.congress.gov
Updated January 20, 2022
Defense Primer: Directed-Energy Weapons
Both the 2018 National Defense Strategy and the House
Armed Services Committee’s bipartisan Future of Defense
Task Force Report have identified directed energy as a
technology that could have a significant impact on U.S.
national security in the years to come. As the Department of
Defense (DOD) continues to invest in directed-energy (DE)
weapons, Congress may consider implications for defense
authorizations, appropriations, and oversight.
Overview
DOD defines DE weapons as those using concentrated
electromagnetic energy, rather than kinetic energy, to
“incapacitate, damage, disable, or destroy enemy
equipment, facilities, and/or personnel.” DE weapons
include high-energy lasers (HEL) and high-powered
microwave (HPM) weapons; other DE weapons, such as
particle beam weapons, are outside the scope of this In
Focus.
HELs might be used by ground forces in short-range air
defense (SHORAD), counter-unmanned aircraft systems
(C-UAS), or counter-rocket, artillery, and mortar (C-RAM)
missions. The weapons might be used to “dazzle” (i.e.,
temporarily disable) or damage satellites and sensors. This
could in turn interfere with intelligence-gathering
operations; military communications; and positioning,
navigation, and timing systems used for weapons targeting.
In addition, HELs could theoretically provide options for
boost-phase missile intercept, given their speed-of-light
travel time; however, experts disagree on the affordability,
technological feasibility, and utility of this application.
In general, HELs might offer lower costs per shot and—
assuming access to a sufficient power supply—deeper
magazines compared with traditional munitions. (Although
a number of different types of HELs exist, many of the
United States’ current programs are solid state lasers, which
are fueled by electrical power. As a result, the cost per shot
is equivalent to the cost of the electrical power required to
fire the shot.) This could in turn produce a favorable cost-
exchange ratio for the defender, whose marginal costs
would be significantly lower than those of the aggressor.
Similarly, HPM weapons could provide a nonkinetic means
of disabling adversary electronics and communications
systems. These weapons could potentially generate effects
over wider areas than HELs, which emit a narrower beam
of energy. As a result, some analysts have noted that HPM
weapons might provide more effective area defense against
missile salvos and swarms of drones. HPM weapons have
also been considered for use as nonlethal “heat ray”
systems for crowd control.
Directed-Energy Weapons Programs
A number of countries are investing in directed-energy
weapons programs. This In Focus discusses a selection of
unclassified DE weapons programs in three leading military
powers: the United States, China, and Russia.
United States
The DOD has a number of DE development programs
underway, requesting at least $578 million in FY2022 for
unclassified DE research, development, test, and evaluation
(RDT&E) and at least $331 million for unclassified DE
weapons procurement. For additional information about
specific U.S. DE weapons programs, see CRS Report
R44175, Navy Lasers, Railgun, and Gun-Launched Guided
Projectile: Background and Issues for Congress, by Ronald
O'Rourke, and CRS Report R45098, U.S. Army Weapons-
Related Directed Energy (DE) Programs: Background and
Potential Issues for Congress, by Andrew Feickert.
Many of these programs are intended to support the Office
of the Under Secretary of Defense for Research and
Engineering’s (OUSD[R&E]) Directed Energy Roadmap.
According to a presentation in 2020 by DOD Principal
Director for Directed Energy Dr. Jim Trebes, who leads the
department’s DE efforts, the roadmap articulates DOD’s
objective of “[achieving] dominance in DE military
applications in every mission and domain where they give
advantage.” The roadmap additionally outlines DOD’s plan
to increase power levels of DE weapons from around 150
kilowatts (kW—a unit of power), as is currently feasible, to
around 300 kW by FY2022, 500 kW by FY2024, and 1
megawatt (MW) by FY2030. For reference, although there
is no consensus regarding the precise power level that
would be needed to neutralize different target sets, some
analysts believe that lasers of around 100 kW could engage
unmanned aircraft systems, small boats, rockets, artillery,
and mortars, whereas lasers of around 300 kW could
additionally engage cruise missiles flying in certain profiles
(i.e., flying across—rather than at—the laser). Lasers of 1
MW could potentially neutralize ballistic missiles and
hypersonic weapons.
In addition to the DE roadmap, OUSD(R&E) manages the
High Energy Laser Scaling Initiative (HELSI), which
Principal Director Trebes notes is “to demonstrate laser
output power scaling while maintaining or improving beam
quality and efficiency.” HELSI is intended to strengthen the
defense industrial base for potential future directed energy
weapons by providing near-term prototyping opportunities
for industry partners. Dr. Trebes additionally notes that
OUSD(R&E) has completed a DOD-wide Laser Lethality
Analysis Process Review to identify future needs for the
Department and best practices for DE development and use
and plans to establish a Directed Energy Lethality Database
