Editing Deterrence theory (section)

{{Short description|Military strategy during the Cold War with regard to the use of nuclear weapons}}
{{About|Deterrent in peace and conflict studies and nuclear weapons|legal theory of justice|Deterrence (penology)}}
[[File:USS Growler SSG-557.jpg|thumb|right|{{USS|Growler|SSG-577|6}}, one of two submarines designed to provide a nuclear deterrence using cruise missiles with a {{convert|500|mi|adj=on}} range—placed on patrol by starting to carry the [[SSM-N-8 Regulus|Regulus I missile]] (shown at Pier 86 in New York, its home as a museum ship)]]
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'''Deterrence theory''' refers to the scholarship and practice of how threats of using force by one party can convince another party to refrain from initiating some other course of action.<ref>{{cite book |title=A Dictionary of Aviation |first=David W. |last=Wragg |isbn=9780850451634 |edition=first |publisher=Osprey |year=1973 |page=108}}</ref> The topic gained increased prominence as a military strategy during the [[Cold War]] with regard to the use of [[nuclear weapons]] and is related to but distinct from the concept of [[mutual assured destruction]], according to which a full-scale nuclear attack on a power with [[second-strike capability]] would devastate both parties. The central problem of deterrence revolves around how to credibly threaten military action or nuclear punishment on the adversary despite its costs to the deterrer.<ref>{{Cite book|last1=Lindsay|first1=Jon R.|url=https://oxford.universitypressscholarship.com/view/10.1093/oso/9780190908645.001.0001/oso-9780190908645-chapter-1|title=Introduction: Cross-Domain Deterrence, from Practice to Theory|last2=Gartzke|first2=Erik|publisher=Oxford University Press|year=2019|isbn=978-0-19-090960-4|pages=2|language=en-US|doi=10.1093/oso/9780190908645.003.0001|access-date=2021-08-30|archive-date=2021-08-30|archive-url=https://web.archive.org/web/20210830211253/https://oxford.universitypressscholarship.com/view/10.1093/oso/9780190908645.001.0001/oso-9780190908645-chapter-1|url-status=live}}</ref> '''Deterrence''' in an [[international relations]] context is the application of deterrence theory to avoid conflict.

Deterrence is widely defined as any use of threats (implicit or explicit) or limited force intended to [[coercive diplomacy|dissuade]] an actor from taking an action (i.e. maintain the status quo).<ref name="Con Ana">{{Cite book|last=Morgan|first=Patrick M.|url=https://books.google.com/books?id=aNreAAAAMAAJ|title=Deterrence: A Conceptual Analysis|date=1977|publisher=SAGE Publications|isbn=978-0-8039-0819-2|pages=26–30|language=en|access-date=2021-08-30|archive-date=2024-02-24|archive-url=https://web.archive.org/web/20240224051622/https://books.google.com/books?id=aNreAAAAMAAJ|url-status=live}}</ref><ref name="Dom Det">{{Cite book|last1=Gartzke|first1=Eric|url=https://oxford.universitypressscholarship.com/view/10.1093/oso/9780190908645.001.0001/oso-9780190908645|title=Cross-Domain Deterrence: Strategy in an Era of Complexity|last2=Lindsay|first2=Jon R.|publisher=Oxford University Press|year=2019|isbn=978-0-19-090960-4|language=en-US|doi=10.1093/oso/9780190908645.001.0001|access-date=2021-08-30|archive-date=2021-08-30|archive-url=https://web.archive.org/web/20210830211242/https://oxford.universitypressscholarship.com/view/10.1093/oso/9780190908645.001.0001/oso-9780190908645|url-status=live}}</ref> Deterrence is unlike [[Coercive diplomacy|compellence]], which is the attempt to get an actor (such as a state) to take an action (i.e. alter the status quo).<ref>{{Cite book|last1=Art|first1=Robert J.|url=https://books.google.com/books?id=Ez8xCgAAQBAJ|title=The Use of Force: Military Power and International Politics|last2=Greenhill|first2=Kelly M.|date=2015|publisher=Rowman & Littlefield Publishers|isbn=978-1-4422-3306-5|pages=3–5|language=en|access-date=2021-08-28|archive-date=2024-02-24|archive-url=https://web.archive.org/web/20240224051621/https://books.google.com/books?id=Ez8xCgAAQBAJ|url-status=live}}</ref><ref name="Arms">{{Cite book|last=Schelling|first=Thomas C.|url=https://www.jstor.org/stable/j.ctt5vm52s|title=Arms and Influence|date=1966|publisher=Yale University Press|doi=10.2307/j.ctt5vm52s |jstor=j.ctt5vm52s|isbn=978-0-300-00221-8|access-date=2021-08-30|archive-date=2022-05-19|archive-url=https://web.archive.org/web/20220519081910/https://www.jstor.org/stable/j.ctt5vm52s|url-status=live}}</ref><ref name="Dom Det" /> Both are forms of [[Coercion (international relations)|coercion]]. Compellence has been characterized as harder to successfully implement than deterrence.<ref name="Arms" /><ref>{{Cite book|last=Pape|first=Robert A.|url=https://www.jstor.org/stable/10.7591/j.ctt1287f6v|title=Bombing to Win: Air Power and Coercion in War|date=1996|publisher=Cornell University Press|isbn=978-0-8014-3134-0|edition=1|jstor=10.7591/j.ctt1287f6v|access-date=2021-08-30|archive-date=2021-08-30|archive-url=https://web.archive.org/web/20210830195841/https://www.jstor.org/stable/10.7591/j.ctt1287f6v|url-status=live}}</ref> Deterrence also tends to be distinguished from [[Military defense|defense]] or the use of full force in wartime.<ref name="Con Ana" />

Deterrence is most likely to be successful when a prospective attacker believes that the probability of success is low and the costs of attack are high.<ref>{{Cite book|last=Mearsheimer|first=John J.|url=https://www.jstor.org/stable/10.7591/j.ctt1rv61v2|title=Conventional Deterrence|date=1983|publisher=Cornell University Press|isbn=978-1-5017-1325-5|pages=23|jstor=10.7591/j.ctt1rv61v2|language=en|access-date=2021-09-05|archive-date=2023-04-05|archive-url=https://web.archive.org/web/20230405171209/https://www.jstor.org/stable/10.7591/j.ctt1rv61v2|url-status=live}}</ref> Central problems of deterrence include the [[Credibility (international relations)|credible]] communication of threats<ref>{{Cite book|last=Shimshoni|first=Jonathan|url=https://www.degruyter.com/document/doi/10.7591/9781501737831/html|title=Israel and Conventional Deterrence|date=1988|publisher=Cornell University Press|isbn=978-1-5017-3783-1|pages=6|language=en|doi=10.7591/9781501737831|s2cid=243305936|access-date=2021-09-06|archive-date=2021-09-06|archive-url=https://web.archive.org/web/20210906141205/https://www.degruyter.com/document/doi/10.7591/9781501737831/html|url-status=live}}</ref><ref name="Dom Det" /> and assurance.<ref>{{Cite news |last1=Glaser |first1=Bonnie S. |last2=Weiss |first2=Jessica Chen |last3=Christensen |first3=Thomas J. |date=2023-11-30 |title=Taiwan and the True Sources of Deterrence |language=en-US |work=Foreign Affairs |url=https://www.foreignaffairs.com/taiwan/taiwan-china-true-sources-deterrence |issn=0015-7120 |access-date=2023-12-01 |archive-date=2023-12-01 |archive-url=https://web.archive.org/web/20231201203915/https://www.foreignaffairs.com/taiwan/taiwan-china-true-sources-deterrence |url-status=live }}</ref> Deterrence does not necessarily require military superiority.<ref name="Act Den">{{Cite journal|last1=Heginbotham|first1=Eric|last2=Samuels|first2=Richard J.|date=2018|title=Active Denial: Redesigning Japan's Response to China's Military Challenge|url=https://doi.org/10.1162/isec_a_00313|journal=International Security|volume=42|issue=4|pages=128–169|doi=10.1162/isec_a_00313|issn=0162-2889|hdl=1721.1/118651|s2cid=57570578|hdl-access=free|access-date=2021-09-06|archive-date=2024-02-24|archive-url=https://web.archive.org/web/20240224051624/https://direct.mit.edu/isec/article-abstract/42/4/128/12190/Active-Denial-Redesigning-Japan-s-Response-to?redirectedFrom=fulltext|url-status=live}}</ref><ref name="Deter" />

"General deterrence" is considered successful when an actor who ''might'' otherwise take an action refrains from doing so due to the consequences that the deterrer is perceived likely to take.<ref name="Sel Eff">{{Cite journal|last=Fearon|first=James|date=2002|title=Selection Effects and Deterrence|url=https://doi.org/10.1080/03050620210390|journal=International Interactions|volume=28|issue=1|pages=5–29|doi=10.1080/03050620210390|s2cid=35580738|issn=0305-0629|access-date=2021-09-06|archive-date=2024-02-24|archive-url=https://web.archive.org/web/20240224051615/https://www.tandfonline.com/doi/abs/10.1080/03050620210390|url-status=live|url-access=subscription}}</ref> "Immediate deterrence" is considered successful when an actor seriously contemplating ''immediate'' military force or action refrains from doing so.<ref name="Sel Eff" /> Scholars distinguish between "extended deterrence" (the protection of allies) and "direct deterrence" (protection of oneself).<ref name="Deter" /><ref>{{Cite journal|last=Lee|first=Do Young|date=2021|title=Strategies of Extended Deterrence: How States Provide the Security Umbrella|journal=Security Studies|volume=30|issue=5|pages=761–796|doi=10.1080/09636412.2021.2010887|s2cid=246241390|issn=0963-6412|doi-access=free}}</ref> Rational deterrence theory holds that an attacker will be deterred if they believe that:<ref>{{Cite book|last=Glaser|first=Charles L.|url=https://books.google.com/books?id=DSoABAAAQBAJ|title=Analyzing Strategic Nuclear Policy|date=1990|publisher=Princeton University Press|isbn=978-1-4008-6202-3|pages=20|language=en|access-date=2021-09-18|archive-date=2023-04-10|archive-url=https://web.archive.org/web/20230410172211/https://books.google.com/books?id=DSoABAAAQBAJ|url-status=live}}</ref><blockquote>(Probability of deterrer carrying out deterrent threat × Costs if threat carried out) > (Probability of the attacker accomplishing the action × Benefits of the action)</blockquote>This model is frequently simplified in [[Game theory|game-theoretic]] terms as:<blockquote>Costs × P(Costs) > Benefits × P(Benefits)

</blockquote>