INSIGHTi

Russia’s Invasion of Ukraine: NATO
Response
February 24, 2022
The 30-member North Atlantic Treaty Organization (NATO) has condemned Russia’s invasion of
Ukraine, describing it as the “most dangerous moment in European security in a generation.” In the lead-
up to the invasion, NATO joined the United States in stating it would not deploy forces to defend Ukraine,
which is not a NATO member. NATO has, however, enhanced its defensive force posture in the eastern
part of the alliance and reiterated its solidarity with Ukraine.
Russia’s invasion follows almost a decade of deteriorating relations between NATO and Russia, during
which NATO suspended most cooperation with Russia following Russia’s 2014 occupation of Ukraine’s
Crimea region and parts of eastern Ukraine. In 2021, NATO declared, “there can be no return to ‘business
as usual’ until Russia demonstrates compliance with international law and its international obligations and
responsibilities.” Noting an end-goal of improved relations, NATO continued to express openness to
political dialogue with Russia as part of a dual-track approach of deterrence and dialogue. NATO officials
stress, however, that by invading Ukraine, “Russia has shut the door on a political solution” to the crisis.
Enhanced Deterrence
Since 2014, NATO has renewed its focus on territorial defense and deterring Russian aggression,
including by deploying battlegroups, increasing military exercises and training, and enhancing air
policing over the Baltic States and Bulgaria and Romania. The cornerstone of these efforts is an Enhanced
Forward Presence (EFP) of four multinational battle groups stationed in the three Baltic States and
Poland. The battle groups, which as of early February 2022 collectively totaled about 5,000 soldiers, are
led by the United Kingdom (Estonia), Canada (Latvia), Germany (Lithuania), and the United States
(Poland). NATO also has established a Multinational Division Southeast headquartered in Romania to
coordinate a Tailored Forward Presence (TFP) in the Black Sea Region.
Several allies—including Denmark, Germany, the Netherlands, Norway, Spain, and the United
Kingdom—have announced additional deployments to bolster NATO’s forward presence. France offered
to lead a new battlegroup in Romania, but plans have yet to be finalized. According to NATO officials, as
of February 24, 2022, more than 100 allied fighter jets were on high alert in the eastern part of the alliance
and more than 120 allied ships were at sea, from the Arctic region to the Mediterranean.
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On February 24, 2022, NATO announced that the alliance had activated defense plans that would allow
military commanders to deploy elements of the NATO Response Force (NRF), a multinational rapid-
reaction force of 40,000 personnel with land, air, maritime, and special operations components. In January
2022, the Biden Administration announced that 8,500 U.S. soldiers would be placed on high readiness for
possible deployment to the NRF.
NATO officials say the allies will further bolster deterrence and defense deployments in response to
Russia’s invasion. The sustainability and effectiveness of NATO’s efforts remain an open question,
however, especially given the size and scope of Russia’s military mobilization. Even prior to Russia’s
invasion, some studies of NATO’s force posture concluded that NATO forces would struggle to defend
NATO’s most vulnerable allies—for example, the Baltic States—from a Russian attack.
U.S. Deterrence Deployments
Following Russia’s 2014 occupation of Crimea, the Obama Administration increased the U.S. military
presence in Europe under the European Reassurance Initiative, later renamed the European Deterrence
Initiative (EDI). The cornerstone of EDI has been Operation Atlantic Resolve, the rotational deployment
of approximately 7,000 U.S. armed forces in Europe, including an Armored Brigade Combat Team (BCT)
in Central and Eastern Europe. In early February 2022, the Biden Administration announced the
deployment of an additional 6,000 soldiers to Central and Eastern Europe. The new deployment brings
the total U.S. military presence in Poland to about 9,500—including 800 soldiers deployed to the U.S.-led
NATO battlegroup—and in Romania to about 1,900. Additional U.S. forces rotate throughout the region,
including about 500 who have been stationed in Lithuania since 2019.
On February 22, 2022, the Department of Defense announced that 800 U.S. soldiers and 20 attack
helicopters would be deployed to the Baltic region, along with 8 F-35 joint strike fighters being deployed
to NATO’s eastern flank. On February 24, the Administration announced that an additional 7,000 U.S.
soldiers, including a BCT, would deploy to Germany to reinforce deterrence efforts.
Considerations for Congress
Members of Congress have condemned Russia’s invasion of Ukraine and expressed support for NATO’s
deterrence posture in Central and Eastern Europe. The evolving crisis raises a number of questions
Congress may wish to consider regarding NATO’s immediate response to Russia’s actions and the longer-
term implications for NATO and U.S. defense policy in Europe. Key considerations include the
following:
 NATO and U.S. Force Posture in Europe. Russia’s invasion could heighten longer-
standing questions about NATO’s capacity to deter and defend NATO member states,
particularly the Baltic States, from a possible Russian military attack. Key factors to
consider could include the willingness and capacity of European allies to increase and
sustain contributions to NATO’s deterrence posture. These questions could inform
congressional decisions on U.S. force posture in Europe, including through the EDI.
 Future of NATO-Russia Relations. NATO’s current Strategic Concept, adopted in
2010, outlines a desire for “strategic partnership” with Russia. As the alliance prepares to
adopt a new Strategic Concept in June 2022, U.S. policymakers could consider
advocating a new NATO approach to Russia, possibly emphasizing defense and
deterrence over cooperation. This may include reassessing NATO’s prior willingness to
negotiate with Russia on European security arrangements, including arms control and the
alliance’s nuclear force posture.

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 NATO Enlargement and Relations with Aspirant States. With support from Congress,
NATO has consistently rejected Russian demands for a halt to NATO enlargement,
underscoring that NATO’s door is open to all European states that aspire to membership
and meet the requisite qualifications. Russia’s invasion of a NATO aspirant that borders
four NATO members could prompt discussions within the alliance on NATO’s
obligations to Ukraine; its relations with other aspirants, such as Georgia; and the future
of NATO enlargement.


Author Information

Paul Belkin

Analyst in European Affairs




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