U.S. Nuclear Weapons Policy: Considering
“No First Use”
Updated October 13, 2021
The Biden Administration began its Nuclear Posture Review (NPR) in July 2021 and expects to complete
the study in early 2021. The NPR is likely to include a review of U.S. declaratory policy—the statements
the United States makes about when, how, and why it might use nuclear weapons to deter adversaries and
reassure U.S. al ies of its commitment to their defense—with a focus on whether the United States should
pledge never to be the first to use nuclear weapons in a conflict. President Biden has spoken, in the past,
about his support for a “sole purpose” policy for nuclear weapons, which some see as similar to a “no first
use” pledge. Some in Congress support such a pledge, but others have insisted that it would undermine
the U.S. commitment to extend deterrence to al ies.
A “no first use” policy would represent a change from current policy, where the United States has pledged
to refrain from using nuclear weapons against most non-nuclear weapon states, but has neither ruled out
their first use in al cases nor specified the circumstances under which it would use them. This policy of
“calculated ambiguity” addressed U.S. concerns during the Cold War, when the United States and NATO
faced numerical y superior Soviet and Warsaw Pact conventional forces in Europe. At the time, the United
States not only developed plans to use nuclear weapons on the battlefield to disrupt or defeat attacking
tanks and troops, but it also hoped that the risk of a nuclear response would deter the Soviet Union from
initiating a conventional attack. This is not because the United States believed it could defeat the Soviet
Union in a nuclear war, but because it hoped the Soviet Union would know that the use of these weapons
would likely escalate to al -out nuclear war, with both sides suffering massive destruction.
Since the end of the Cold War, the United States has modified its declaratory policy to reduce the apparent
role of nuclear weapons in U.S. national security, but has not declared that it would not use them first. In
the 2010 Nuclear Posture Review Report, the Obama Administration stated that the United States “would
only consider the use of nuclear weapons in extreme circumstances” and would not threaten or use
nuclear weapons, under any circumstances, “against non-nuclear weapons states that are party to the
Nuclear Nonproliferation Treaty and in compliance with their nuclear non-proliferation obligations.” But
the Administration was not prepared to state that the “sole purpose” of U.S. nuclear weapons was to deter
nuclear attack because it could envision “a narrow range of contingencies” where nuclear weapons might
play a role in deterring conventional, chemical, or biological attacks.
The Trump Administration, in the 2018 Nuclear Posture Review (NPR) Report, also rejected the idea that
the sole purpose of nuclear weapons is to deter nuclear attack, and, therefore, did not adopt a “no first
use” policy. It noted that “the United States would only consider the employment of nuclear weapons in
extreme circumstances to defend the vital interests of the United States, its al ies, and partners” but stated
that nuclear weapons contribute to “deterrence of nuclear and non-nuclear attack; assurance of al ies and

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Congressional Research Service
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partners; achievement of U.S. objectives if deterrence fails; and the capacity to hedge against an uncertain
future.”
“No First Use” or Not?
Although the United States does not rule out the first use of nuclear weapons, the absence of a “no first
use” pledge is less about the perceived need to employ these weapons first in a conflict than it is about the
view that the threat of nuclear escalation continues to serve as a deterrent to large-scale conventional war
or the use of chemical and biological weapons. Supporters of the current policy argue that removing the
threat of nuclear escalation could embolden countries like North Korea, China, or Russia, who might
believe that they could overwhelm U.S. al ies in their regions and take advantage of local or regional
conventional advantages before the United States or its al ies could respond. In such a scenario, some
argue, the “no first use” pledge would not only undermine deterrence, but could also increase the risk that
a conventional war could escalate and involve nuclear weapons use. Moreover, because the United States
has pledged to use al means necessary, including nuclear weapons, to defend al ies in Europe and Asia,
this change in U.S. declaratory policy could undermine al ies’ confidence in the U.S. commitment to their
defense and possibly spur them to acquire their own nuclear weapons. As a result, in this view, a “no first
use” policy could undermine U.S. nuclear nonproliferation goals.
Some analysts outside government dispute these conclusions. Some assert that there is a lack of evidence
that the threat of nuclear escalation can deter conventional war, while others note that U.S. nuclear first-
use might spark a nuclear response and an al -out nuclear exchange. Moreover, some contend that “no
first use” would not undermine the U.S. commitment to its al ies because those states have faith in U.S.
conventional forces for their defense, as wel as knowledge of the U.S. wil ingness to retaliate with
nuclear weapons in response to nuclear attacks. Others note that a “no first use” pledge could reduce the
chances of nuclear miscalculation by assuring adversaries that the United States was not about to launch a
preemptive nuclear attack. Hence, many conclude that the possible first use of nuclear weapons is not
only unnecessary, but also might turn conventional war into a nuclear catastrophe.
Press reports indicate that the Obama Administration considered adopting a “no first use” policy in 2016.
However, these reports indicate that both military and civilian officials opposed this change. Some argued
that a policy of calculated ambiguity provided the President with options in a crisis; others noted that the
shift could undermine deterrence and stability in an uncertain security environment. Secretary of State
Kerry and Secretary of Defense Carter also raised concerns that a “no first use” policy could undermine
the confidence and security of U.S. al ies. Secretary of Energy Moniz also expressed opposition. Reports
indicate that several al ies also weighed in against the change in policy.


Author Information

Amy F. Woolf

Specialist in Nuclear Weapons Policy




Disclaimer

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IN10553 · VERSION 5 · UPDATED

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