Defense Primer: Geography, Strategy, and U.S. Force Design
Updated March 19, 2024
Defense Primer: Geography, Strategy, and U.S. Force Design
World geography is an influence on U.S. strategy, which in
structured with force elements that enable it to deploy from
turn helps shape the design of U.S. military forces.
the United States, cross broad expanses of ocean and air
space, and then conduct sustained, large-scale military
World Geography and U.S. Strategy
operations upon arrival in Eurasia or the waters and
Most of the world’s people, resources, and economic
airspace surrounding Eurasia. Force elements associated
activity are located not in the Western Hemisphere, but in
with this objective include, among other things
the other hemisphere, particularly Eurasia. In response to
this basic feature of world geography, U.S. policymakers
• An Air Force with significant numbers of long-range
for the last several decades have chosen to pursue, as a key
bombers, long-range surveillance aircraft, and aerial
element of U.S. national strategy, a goal of preventing the
refueling tankers.
emergence of regional hegemons in Eurasia. This objective
reflects a U.S. perspective on geopolitics and grand strategy
• A Navy with significant numbers of aircraft carriers,
developed by U.S. strategists and policymakers during and
nuclear-powered (as opposed to non-nuclear-powered)
in the years immediately after World War II that
attack submarines, large surface combatants, large
incorporates two key judgments:
amphibious ships, and underway replenishment ships.
• that given the amount of people, resources, and
• Significant numbers of long-range Air Force airlift
economic activity in Eurasia, a regional hegemon in
aircraft and Military Sealift Command sealift ships for
Eurasia would represent a concentration of power large
transporting ground forces personnel and their
enough to be able to threaten vital U.S. interests; and
equipment and supplies rapidly over long distances.
• that Eurasia is not dependably self-regulating in terms of Consistent with a goal of being able to conduct sustained,
preventing the emergence of regional hegemons,
large-scale military operations in Eurasia or the oceans and
meaning that the countries of Eurasia cannot be counted
airspace surrounding Eurasia, the United States also stations
on to be fully able to prevent, through their own choices
significant numbers of forces and supplies in forward
and actions, the emergence of regional hegemons, and
locations in Europe, the Indo-Pacific, and the Persian Gulf.
may need assistance from one or more countries outside
Eurasia to be able to do this dependably.
Comparing U.S. Forces to Other
Countries’ Forces
Preventing the emergence of regional hegemons in Eurasia
The United States is the only country in the world that
is sometimes also referred to as preserving a division of
designs its military to be able to depart one hemisphere,
power in Eurasia, or as preventing key regions in Eurasia
cross broad expanses of ocean and air space, and then
from coming under the domination of a single power, or as
conduct sustained, large-scale military operations upon
preventing the emergence of a spheres-of-influence world,
arrival in another hemisphere. The other countries in the
which could be a consequence of the emergence of one or
Western Hemisphere do not design their forces to do this
more regional hegemons in Eurasia. The Biden
because they cannot afford to, and because the United
Administration’s October 2022 National Security Strategy
States is, in effect, doing it for them. Countries in the other
document states: “The United States is a global power with
hemisphere do not design their forces to do this for the very
global interests. We are stronger in each region because of
basic reason that they are already in the other hemisphere,
our affirmative engagement in the others. If one region
and consequently instead spend their defense money
descends into chaos or is dominated by a hostile power, it
primarily on forces that are tailored largely for influencing
will detrimentally impact our interests in the others.”
events in 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
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Defense Primer: Geography, Strategy, and U.S. Force Design
sustained, large-scale military aircraft operations upon
The U.S. military is currently sized to be able to conduct
arrival in distant locations.
something less than two simultaneous or overlapping major
conflicts. Great power competition with China and Russia
As another example, it is sometimes noted, in assessing the
has prompted some observers to ask whether the force-
adequacy of U.S. naval forces, that U.S. naval forces are
planning standard should be changed to being able to fight
equal in tonnage to the next several navies combined, and
two simultaneous or overlapping major conflicts—a so-
that most of those several navies are the navies of U.S.
called two-war or two-major-war standard. Discussions of
allies. Those other fleets, however, are mostly of Eurasian
this issue may also consider the need for U.S. forces for
countries, which do not design their forces to cross to the
deterring or responding to challenges to U.S. interests in the
other side of the world and then conduct sustained, large-
Middle East from actors other than China and Russia.
scale military operations upon arrival in distant locations.
Indo-Pacific Compared to Europe
The fact that the U.S. Navy is much bigger than allied
The differing geographic natures of the Indo-Pacific region
navies does not necessarily prove that U.S. naval forces are
(meaning East and South Asia and the adjoining Pacific and
either sufficient or excessive; it simply reflects the differing
Indian oceans) and Europe can affect U.S. force design. For
and generally more limited needs that U.S. allies have for
the U.S. military, the Indo-Pacific is viewed as more of a
naval forces. (It might also reflect an underinvestment by
maritime and aerospace theater of operations, meaning a
some of those allies to meet even their more limited naval
theater where naval forces (i.e., the Navy and Marine
needs.)
Corps) and the Air Force are more predominant, while
Measuring the Sufficiency of U.S. Forces
Europe is viewed as more of a continental or land-oriented
Countries have differing needs for military forces. The
theater of operations, meaning a theater where the Army
United States, as a country located in the Western
and the Air Force are more predominant. A choice by U.S.
Hemisphere with a goal of preventing the emergence of
policymakers to put more emphasis on one of these theaters
regional hegemons in Eurasia, has defined a need for
than the other can thus affect the composition of U.S.
military forces that is quite different from the needs of
military forces.
countries that are located in Eurasia. The sufficiency of
Strategy Is a Policy Choice, Force Design
U.S. military forces consequently is best assessed not
Is a Consequence
through comparison to the militaries of other countries
That U.S. policymakers for the past several decades have
(something that is done quite frequently), but against U.S.
chosen to pursue, as a key element of U.S. national strategy,
strategic goals, which in turn reflect U.S. policymaker
a goal of preventing the emergence of regional hegemons in
judgments about the United States’ role in the world.
Eurasia does not necessarily mean this goal was a correct
Force-Planning Standard
one for the United States to pursue, or that it would be a
The geography of Eurasia itself is a factor in U.S. force
correct one for the United States to pursue in the future.
design in relation to the force-planning standard, meaning
Whether it would be a correct one for the United States to
the number and types of simultaneous or overlapping
pursue in the future would depend on policymaker views
conflicts or other contingencies that the U.S. military
regarding the two key judgments outlined earlier. A
should be sized to be able to conduct—a planning factor
decision on whether to continue pursuing such a goal would
that can strongly impact the size of the U.S. defense budget.
then influence U.S. military force design for the future.
(Other terms for referring to the force-planning standard use
force-sizing instead of force-planning, and construct or
CRS Products
metric instead of standard.) Eurasia includes three regions
CRS Report R43838, Great Power Competition: Implications for
of particular interest to U.S. policymakers and military
Defense—Issues for Congress, by Ronald O'Rourke.
force planners—East Asia (where potential adversaries
include China and North Korea), Southwest Asia (which
includes potential adversaries such as Iran), and Europe
(where the potential adversary is Russia). The question is
Other Resources
what force-planning standard to adopt, given U.S. interests
White House, National Security Strategy, October 2022, 48 pp.,
in these three regions of Eurasia.
accessed November 15, 2022, at https://www.whitehouse.gov/
wp-content/uploads/2022/10/Biden-Harris-Administrations-
Following the end of the Cold War, U.S. military forces
National-Security-Strategy-10.2022.pdf.
were sized to be able to fight and win two overlapping
major regional conflicts or major regional contingencies
Department of Defense, 2022 National Defense Strategy of
(MRCs), the logic being that sizing the U.S. military to be
the United States of America, Including the 2022 Nuclear
able to fight no more than one MRC at a time could tempt
Posture Review and the 2022 Missile Defense Review, cover
an adversary to act aggressively in one region if U.S. forces
letter dated October 27, 2022, 80 pp., accessed November
were already committed to countering aggression by
15, 2022, at https://media.defense.gov/2022/Oct/27/
another adversary in a different region. In subsequent years,
2003103845/-1/-1/1/2022-NATIONAL-DEFENSE-STRATEGY-
the U.S. force-planning standard was reduced to what was
NPR-MDR.PDF.
referred to as a win-hold standard, meaning an ability to
fight and win one MRC while conducting a holding action
in a second MRC. Under the win-hold standard, the United
States, after winning the first MRC, would redeploy forces
Ronald O'Rourke, Specialist in Naval Affairs
from the first MRC to augment those already involved in
the second MRC.
IF10485
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Defense Primer: Geography, Strategy, and U.S. Force Design
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