Defender Europe 20 Military Exercise, Historical (REFORGER) Exercises, and U.S. Force Posture in Europe
January 14, 2020
Defender 2020-Europe Military Exercise, Historical
(REFORGER) Exercises, and U.S. Force Posture in Europe
On October 7, 2019, the U.S. Army announced it would
represented
approximately
193,000
soldiers
conduct the largest U.S.-based exercise of forces deploying
organized under two corps (each composed of an
to Europe in the past 25 years: Defender 2020-Europe.
armored division, an infantry division, and an
While some have compared it to annual Cold War-era
armored cavalry brigade) in addition to three
REFORGER military exercises, the Army suggests that
independent combat brigades and numerous enabler
while similar, Defender 2020-Europe will be a more
and support units. Apart from permanent-stationed
complex exercise than historical REFORGER exercises in
forces, the United States maintained large
terms of logistics, multinational command and control, and
stockpiles of prepositioned equipment in Western
multidomain operations.
Europe—enough for several divisions and support
Defender 2020-Europe
units—to allow forces based elsewhere to rapidly
reinforce the continent in the event of conflict.
From a military standpoint, in the event of a major conflict
on the European continent, present force levels, including
The Evolution of REFORGER
units in Europe as part of the “heel-to-toe” rotations, could
According to the Government Accountability Office
prove to be insufficient to defend U.S. and allied interests.
(GAO):
In that scenario, the United States may choose to flow
significant additional forces across the Atlantic, an
REFORGER’S history can be traced to the 1967
undertaking that would be complex under optimal
Tripartite Agreement between the United States, the
circumstances, and exponentially more so under conditions
United Kingdom, and the Federal Republic of
of war, when an adversary might seek to actively prevent
Germany. The agreement allowed the United States
the arrival of U.S. forces and equipment (“anti-access/area
to bring back to the United States the headquarters
denial”). Some officials are concerned that the United
and two brigades of the 24th Mechanized Infantry
States’ ability to move equipment in timely fashion, in
Division, leaving only one brigade of that division
particular heavy tanks and fighting vehicles, from U.S.
in Europe. To compensate for this reduction in
bases to the ports from which the equipment is shipped
troop strength, the agreement required that U.S.
requires additional emphasis. Defender-2020 is intended to
forces returning to the United States be held in a
exercise and test such expeditionary deployment
high state of readiness to ensure their capability to
capabilities, much as REFORGER did in past eras.
return rapidly to Europe in a crisis. The agreement
What Was REFORGER?
also stipulated that the 24th Mechanized Infantry
Division return the two U.S.-based brigades
REFORGER—REturn of FORces to GERmany—was a
annually
to
Germany,
draw
prepositioned
series of North Atlantic Treaty Organization (NATO)
equipment, link up with the forward-deployed
annual military exercises conducted from the late 1960s to
brigade, and then participate in a field training
early 1990s to validate the ability of NATO allies to rapidly
exercise (FTX).
deploy forces to Europe to reinforce NATO positions on the
continent and to demonstrate Western commitment to
REFORGER was conducted in three phases:
defend against Warsaw Pact aggression.
(1) Deployment. Tested procedures for receiving,
U.S. Military in Europe During the Cold War
equipping, and transporting REFORGER units to assembly
areas for tactical employment and also evaluated the condition
While approximately 74,000 U.S. military personnel are
of prepositioned equipment.
stationed in Europe today, at the height of the Cold War,
(2) REFORGER Follow-On Exercise. Provided combined
more than 400,000 U.S. military personnel were stationed
arms training to REFORGER forces and oriented units
on the European continent. According to the Center for
deployed from the United States with the European
Strategic and International Studies (CSIS):
environment, as well as their missions in the defense of
Europe.
In the late 1980s, the United States maintained
approximately 340,000 permanently stationed
(3) Redeployment. Cleaned equipment, returned it to
military personnel in Europe to deter the
storage, and redeploy forces back to the United States.
conventional threat that the Soviet Union and
While REFORGER initially enjoyed public support, as the
Warsaw Pact forces posed to West Germany and
exercise grew over the years in terms of numbers of troops
Western Europe. Of that, U.S. Army forces
and quantities of equipment, and overall exercise scope,
https://crsreports.congress.gov
Defender 2020-Europe Military Exercise, Historical (REFORGER) Exercises, and U.S. Force Posture in Europe
public opposition in Europe over the disruptive nature of
capable missiles to Kaliningrad (a Russian territory on the
the two-month or longer exercise and the damage it caused
Baltic Sea that is not contiguous with Russia itself),
to the environment became more pronounced. In addition,
enhancing its air patrolling activities close to other states’
the costs associated with airlift, sealift, port handling, and
airspace, and enhancing its naval presence in the Baltic Sea,
inland transportation of troops and equipment, as well as
the Arctic Ocean, and the North Sea. Taken together, these
payments to European governments and citizens for
moves have heightened some congressional concerns about
maneuver damage, became more of a consideration. Based
Russian aggression and its implications for NATO
in part on the aforementioned concerns, starting in 1989,
territories, particularly among Central and Eastern
when the U.S. decided to cancel REFORGER and replace it
European NATO allies.
with a smaller command post exercise, REFORGER began
evolving to more of a computer simulation-based command
The European Deterrence Initiative and
post exercise that involved fewer troops, less equipment,
Operation Atlantic Resolve
and not as much maneuver. As the threat from the Warsaw
In response, the United States and its NATO allies have
Pact began to diminish in the early 1990s, REFORGER
undertaken a number of initiatives to underscore NATO’s
exercises were scaled back, with the last REFORGER
collective defense agreements, intended to assure allies of
exercise being held in 1993.
their own security while simultaneously deterring Russian
From 1993 to 2014
aggression. The United States has bolstered security in
Central and Eastern Europe with an increased rotational
For nearly 20 years after the collapse of the Soviet Union,
military presence, additional exercises and training with
several strategic assumptions guided U.S. policy:
allies and partners, improved infrastructure to allow greater
responsiveness, enhanced prepositioning of U.S.
Europe could be stable, whole, and free;
equipment, and intensified efforts to build partner capacity
Russia could be a constructive partner in the Euro-
for newer NATO members and other non-NATO countries.
Atlantic security architecture; and
The European Deterrence Initiative (EDI), launched in 2014
particularly prior to September 11, 2001, threats posed
(originally called the European Reassurance Initiative), an
by terrorism and migration from the Middle East/North
Overseas Contingency Operations set of programs in the
Africa region were limited.
U.S. defense budget, is the key means of building partner
These assumptions led to the withdrawal of the bulk of
capacity. U.S. military operational activities of EDI are
forward-deployed U.S. troops in the European theater.
executed as part of Operation Atlantic Resolve (OAR).
USEUCOM subsequently focused on nonwarfighting
Approximately 6,000 U.S. military personnel are involved
missions—some of them outside of NATO’s traditional
in OAR at any given time, with units typically operating in
area of operations. Such missions included building the
the region under a rotational nine-month deployment.
security capacity and capability of former Soviet bloc
As part of OAR, DOD has also increased its rotations of
states; prosecuting “crisis management” operations in the
temporary forces in and out of USEUCOM to assure allies
Balkans; and logistically supporting U.S. Central Command
of the United States’ commitment to their security. Dubbed
and U.S. Africa Command by providing, in particular,
“heel-to-toe” rotations, air, ground and naval assets are
critical medical evacuation facilities using U.S. bases in
deployed from the United States to conduct exercises with
Germany.
NATO allies for several months; they are then immediately
Over the past 25 years, decisions regarding U.S. basing and
replaced by other like units. U.S. ground forces have been
posture in the European theater largely reflected these
largely stationed in Poland, with elements also conducting
assumptions. The bulk of U.S. forces in Europe were
training and exercises in the Baltic States, Bulgaria,
withdrawn (as of FY2018, approximately 74,000 military
Romania, and Germany. This rotation ensures that there are
service members were assigned and 20,000 civilians were
at least three Brigade Combat Teams in Europe at all times.
authorized to USEUCOM and its subordinate commands).
Many observers contend these “heel-to-toe” rotations have
Many bases and outposts were either consolidated or
usefully required military units in the continental United
closed. Nevertheless, two Brigade Combat Teams (BCTs)
States to routinely test their ability to deploy to other
were retained (in Italy and Germany), as were some naval
theaters and exercise critical logistics and mobility
bases, particularly those along NATO’s southern flank, and
capabilities. After nearly 20 years of expeditionary
a number of air bases that were deemed critical for
operations in the Middle East region, the skills and
supporting operations in the Middle East, Africa, and
capabilities necessary to mass U.S. forces onto the
Europe.
European continent and transit them to the front lines have
USEUCOM’s Current
arguably atrophied. Heel-to-toe rotations have allowed U.S.
Geopolitical Challenges
forces to develop those skills while simultaneously
identifying and developing solutions to logistical issues in
Events in recent years, particularly since 2014, have tested,
Eastern Europe that might slow down a U.S./NATO
if not undermined, the strategic assumptions underpinning
response to a crisis.
USEUCOM’s posture. To Europe’s east, Russia annexed
Andrew Feickert, Specialist in Military Ground Forces
Crimea, began a proxy war in Eastern Ukraine, and is
modernizing its conventional and nonconventional forces.
Kathleen J. McInnis, Specialist in International Security
Russia also increased its military activities in Europe’s high
IF11407
north, particularly through reportedly adding nuclear-
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Defender 2020-Europe Military Exercise, Historical (REFORGER) Exercises, and U.S. Force Posture in Europe
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