Updated October 25, 2021
Defense Primer: Geography, Strategy, and U.S. Force Design
World geography is an influence on U.S. strategy, which in
space, and then conduct sustained, large-scale military
turn helps shape the design of U.S. military forces.
operations upon arrival in Eurasia or the waters and
airspace surrounding Eurasia. Force elements associated
World Geography and U.S. Strategy
with this objective include, among other things:
Most of the world’s people, resources, and economic
activity are located not in the Western Hemisphere, but in
An Air Force with significant numbers of long-range
the other hemisphere, particularly Eurasia. In response to
bombers, long-range surveillance aircraft, and aerial
this basic feature of world geography, U.S. policymakers
refueling tankers.
for the last several decades have chosen to pursue, as a key
element of U.S. national strategy, a goal of preventing the
A Navy with significant numbers of aircraft carriers,
emergence of regional hegemons in Eurasia. This objective
nuclear-powered (as opposed to non-nuclear-powered)
reflects a U.S. perspective on geopolitics and grand strategy
attack submarines, large surface combatants, large
developed by U.S. strategists and policymakers during and
amphibious ships, and underway replenishment ships.
in the years immediately after World War II that
incorporates two key judgments:
Significant numbers of long-range Air Force airlift
aircraft and Military Sealift Command sealift ships for
that given the amount of people, resources, and
transporting ground forces personnel and their
economic activity in Eurasia, a regional hegemon in
equipment and supplies rapidly over long distances.
Eurasia would represent a concentration of power large
enough to be able to threaten vital U.S. interests; and
Consistent with a goal of being able to conduct sustained,
large-scale military operations in Eurasia or the oceans and
that Eurasia is not dependably self-regulating in terms of airspace surrounding Eurasia, the United States also stations
preventing the emergence of regional hegemons,
significant numbers of forces and supplies in forward
meaning that the countries of Eurasia cannot be counted
locations in Europe, the Persian Gulf, and the Indo-Pacific.
on to be fully able to prevent, through their own choices
On February 4, 2021, President Biden announced that
and actions, the emergence of regional hegemons, and
“Defense Secretary Austin will be leading a Global Posture
may need assistance from one or more countries outside
Review of our forces so that our military footprint is
Eurasia to be able to do this dependably.
appropriately aligned with our foreign policy and national
security priorities.” DOD stated that the review “will
Preventing the emergence of regional hegemons in Eurasia
examine the U.S. military’s footprint, resources and
is sometimes also referred to as preserving a division of
strategies” and “will use American defense strategy and
power in Eurasia, or as preventing key regions in Eurasia
look where service members are based, and if this is the
from coming under the domination of a single power, or as
best place to be based.”
preventing the emergence of a spheres-of-influence world,
which could be a consequence of the emergence of one or
Comparing U.S. Forces to Other
more regional hegemons in Eurasia. The Trump
Countries’ Forces
Administration’s December 2017 national security strategy
The United States is the only country in the world that
document states that the United States “will compete with
designs its military to depart one hemisphere, cross broad
all tools of national power to ensure that regions of the
expanses of ocean and air space, and then conduct
world are not dominated by one power.”
sustained, large-scale military operations upon arrival in
another hemisphere. The other countries in the Western
Although U.S. policymakers do not often state explicitly in
Hemisphere do not design their forces to do this because
public the goal of preventing the emergence of regional
they cannot afford to, and because the United States is, in
hegemons in Eurasia, U.S. military operations in World
effect, doing it for them. Countries in the other hemisphere
War I and World War II, as well as numerous U.S. military
do not design their forces to do this for the very basic
wartime and day-to-day operations since World War II (and
reason that they are already in the other hemisphere, and
nonmilitary elements of U.S. national strategy since World
consequently instead spend their defense money primarily
War II), appear to have been carried out in no small part in
on forces that are tailored largely for influencing events in
support of this goal.
their own local regions of that hemisphere. (Some
countries, such as Russia, China, the United Kingdom, and
U.S. Strategy and Force Design
France, have an ability to deploy forces to distant locations,
The goal of preventing the emergence of regional hegemons
but only on a much smaller scale.)
in Eurasia is a major reason why the U.S. military is
structured with force elements that enable it to deploy from
The fact that the United States designs its military to do
the United States, cross broad expanses of ocean and air
something that other countries do not design their forces to
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Defense Primer: Geography, Strategy, and U.S. Force Design
do can be important to keep in mind when comparing the
The Biden Administration may choose to review the
U.S. military to the militaries of other nations. For example,
question of whether the United States should continue to
the U.S. Navy has 11 aircraft carriers while other countries
pursue, as a key element of U.S. national strategy, a goal of
have no more than one or two. Other countries do not need
preventing the emergence of regional hegemons in Eurasia.
a significant number of aircraft carriers because, unlike the
A decision on whether to continue pursuing such a goal
United States, they are not designing their forces to cross
would then influence U.S. military force design for the
broad expanses of ocean and air space and then conduct
future.
sustained, large-scale military aircraft operations upon
arrival in distant locations.
January 19, 2021, Testimony by Lloyd
Austin
As another example, it is sometimes noted, in assessing the
At a January 19, 2021, hearing before the Senate Armed
adequacy of U.S. naval forces, that U.S. naval forces are
Services Committee on the nomination of retired General
equal in tonnage to the next several navies combined, and
Lloyd Austin to be Secretary of Defense, Senator Angus
that most of those several navies are the navies of U.S.
King asked Austin: “What do you believe China’s strategic
allies. Those other fleets, however, are mostly of Eurasian
goals are? Are they looking to be the dominant world power
countries, which do not design their forces to cross to the
or regional hegemon? An economic power? What is their—
other side of the world and then conduct sustained, large-
what are their goals?” Austin replied (emphasis added):
scale military operations upon arrival in distant locations.
“Yeah, I think it’s all of that. They’re already a regional
The fact that the U.S. Navy is much bigger than allied
hegemon and I think their goal is to be a dominant world
navies does not necessarily prove that U.S. naval forces are
power.”
either sufficient or excessive; it simply reflects the differing
and generally more limited needs that U.S. allies have for
CRS Products
naval forces. (It might also reflect an underinvestment by
some of those allies to meet even their more limited naval
CRS In Focus IF11798, The Interim National Security Strategic
needs.)
Guidance, by Kathleen J. McInnis
CRS Report R43838, Renewed Great Power Competition:
Measuring the Sufficiency of U.S. Forces
Implications for Defense—Issues for Congress, by Ronald
Countries have differing needs for military forces. The
O'Rourke
United States, as a country located in the Western
CRS Report R46336, COVID-19: Potential Implications for
Hemisphere with a goal of preventing the emergence of
International Security Environment—Overview of Issues and
regional hegemons in Eurasia, has defined a need for
Further Reading for Congress, by Ronald O'Rourke and Kathleen
military forces that is quite different from the needs of
J. McInnis
countries that are located in Eurasia. The sufficiency of
U.S. military forces consequently is best assessed not
through comparison to the militaries of other countries
(something that is done quite frequently), but against U.S.
Other Resources
strategic goals, which in turn reflect U.S. policymaker
White House, Interim National Security Strategic Guidance,
judgments about the United States’ role in the world.
March 2021, 23 pp., accessed June 9, 2021, at
https://www.whitehouse.gov/wp-
Strategy Is a Policy Choice, Force Design
content/uploads/2021/03/NSC-1v2.pdf
Is a Consequence
Department of Defense, Summary of the 2018 National Defense
The fact that U.S. policymakers for the last several decades
Strategy of the United States of America, Sharpening the American
have chosen to pursue, as a key element of U.S. national
Military’s Competitive Edge, undated, released January 19, 2018,
strategy, a goal of preventing the emergence of regional
11 pp., accessed June 9, 2021, at https://www.defense.gov/
hegemons in Eurasia, does not necessarily mean that this
Portals/1/Documents/pubs/2018-National-Defense-Strategy-
goal was a correct one for the United States to pursue, or
Summary.pdf.
that it would be a correct one for the United States to pursue
in the future. Whether it would be a correct one for the
United States to pursue in the future would depend on
policymaker views regarding the two key judgments
outlined earlier.
Ronald O'Rourke, Specialist in Naval Affairs
IF10485
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Defense Primer: Geography, Strategy, and U.S. Force Design
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