Defense Primer: Geography, Strategy, and U.S. Force Design

Updated June 9, 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, though their own choices
and actions, the emergence of regional hegemons, and
Comparing U.S. Forces to Other
may need assistance from one or more countries outside
Countries’ Forces
Eurasia to be able to do this dependably.
The United States is the only country in the world that
designs its military to depart one hemisphere, cross broad
Preventing the emergence of regional hegemons in Eurasia
expanses of ocean and air space, and then conduct
is sometimes also referred to as preserving a division of
sustained, large-scale military operations upon arrival in
power in Eurasia, or as preventing key regions in Eurasia
another hemisphere. The other countries in the Western
from coming under the domination of a single power, or as
Hemisphere do not design their forces to do this because
preventing the emergence of a spheres-of-influence world,
they cannot afford to, and because the United States is, in
which could be a consequence of the emergence of one or
effect, doing it for them. Countries in the other hemisphere
more regional hegemons in Eurasia. The Trump
do not design their forces to do this for the very basic
Administration’s December 2017 national security strategy
reason that they are already in the other hemisphere, and
document states that the United States “will compete with
consequently instead spend their defense money primarily
all tools of national power to ensure that regions of the
on forces that are tailored largely for influencing events in
world are not dominated by one power.”
their own local regions of that hemisphere. (Some
countries, such as Russia, China, the United Kingdom, and
Although U.S. policymakers do not often state explicitly in
France, have an ability to deploy forces to distant locations,
public the goal of preventing the emergence of regional
but only on a much smaller scale.)
hegemons in Eurasia, U.S. military operations in World
War I and World War II, as well as numerous U.S. military
The fact that the United States designs its military to do
wartime and day-to-day operations since World War II (and
something that other countries do not design their forces to
nonmilitary elements of U.S. national strategy since World
do can be important to keep in mind when comparing the
War II), appear to have been carried out in no small part in
U.S. military to the militaries of other nations. For example,
support of this goal.
the U.S. Navy has 11 aircraft carriers while other countries
have no more than one or two. Other countries do not need
U.S. Strategy and Force Design
a significant number of aircraft carriers because, unlike the
The goal of preventing the emergence of regional hegemons
United States, they are not designing their forces to cross
in Eurasia is a major reason why the U.S. military is
broad expanses of ocean and air space and then conduct
structured with force elements that enable it to deploy from
sustained, large-scale military aircraft operations upon
the United States, cross broad expanses of ocean and air
arrival in distant locations.

Defense Primer: Geography, Strategy, and U.S. Force Design
As another example, it is sometimes noted, in assessing the
would then influence U.S. military force design for the
adequacy of U.S. naval forces, that U.S. naval forces are
equal in tonnage to the next several navies combined, and
that most of those several navies are the navies of U.S.
January 19, 2021, Testimony by Lloyd
allies. Those other fleets, however, are mostly of Eurasian
countries, which do not design their forces to cross to the
At a January 19, 2021, hearing before the Senate Armed
other side of the world and then conduct sustained, large-
Services Committee on the nomination of retired General
scale military operations upon arrival in distant locations.
Lloyd Austin to be Secretary of Defense, Senator Angus
The fact that the U.S. Navy is much bigger than allied
King asked Austin: “What do you believe China’s strategic
navies does not necessarily prove that U.S. naval forces are
goals are? Are they looking to be the dominant world power
either sufficient or excessive; it simply reflects the differing
or regional hegemon? An economic power? What is their—
and generally more limited needs that U.S. allies have for
what are their goals?” Austin replied (emphasis added):
naval forces. (It might also reflect an underinvestment by
“Yeah, I think it’s all of that. They’re already a regional
some of those allies to meet even their more limited naval
hegemon and I think their goal is to be a dominant world
Measuring the Sufficiency of U.S. Forces
CRS Products
Countries have differing needs for military forces. The
United States, as a country located in the Western
CRS Report R43838, Renewed Great Power Competition:
Hemisphere with a goal of preventing the emergence of
Implications for Defense—Issues for Congress, by Ronald
regional hegemons in Eurasia, has defined a need for
military forces that is quite different from the needs of
CRS Report R46336, COVID-19: Potential Implications for
countries that are located in Eurasia. The sufficiency of
International Security Environment—Overview of Issues and
U.S. military forces consequently is best assessed not
Further Reading for Congress, by Ronald O'Rourke and Kathleen
through comparison to the militaries of other countries
J. McInnis
(something that is done quite frequently), but against U.S.
strategic goals, which in turn reflect U.S. policymaker

judgments about the U.S. role in the world.
Other Resources
Strategy Is a Policy Choice, Force Design
White House, Interim National Security Strategic Guidance,
Is a Consequence
March 2021, 23 pp., accessed June 9, 2021, at
The fact that U.S. policymakers for the last several decades
have chosen to pursue, as a key element of U.S. national
strategy, a goal of preventing the emergence of regional
Department of Defense, Summary of the 2018 National Defense
hegemons in Eurasia, does not necessarily mean that this
Strategy of the United States of America, Sharpening the American
goal was a correct one for the United States to pursue, or
Military’s Competitive Edge, undated, released January 19, 2018,
that it would be a correct one for the United States to pursue
11 pp., accessed June 9, 2021, at
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.

The Biden Administration may choose to review the
Ronald O'Rourke, Specialist in Naval Affairs
question of whether the United States should continue to
pursue, as a key element of U.S. national strategy, a goal of
preventing the emergence of regional hegemons in Eurasia.
A decision on whether to continue pursuing such a goal

Defense Primer: Geography, Strategy, and U.S. Force Design

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