Nuclear holocaust

==Likelihood of nuclear war==
{{See also|World War III#Historical close calls}}
[[File:World nuclear weapons.svg|thumb|Large stockpile with global range (dark blue), smaller stockpile with global range (medium blue), small stockpile with regional range (light blue)]]
As of 2021, humanity has about 13,410 nuclear weapons, thousands of which are on [[De-alerting|hair-trigger alert]].<ref>{{cite web|title=Status of World Nuclear Forces|url= https://fas.org/issues/nuclear-weapons/status-world-nuclear-forces/ |website=Federation of American Scientists|access-date=26 April 2020}}</ref><ref>{{cite web|title=Fact Sheet: Building Global Security by Taking Nuclear Weapons off Hair-Trigger Alert|url=http://www.nti.org/analysis/articles/fact-sheet-building-global-security-taking-nuclear-weapons-hair-trigger-alert/|publisher=[[National Threat Initiative]]|access-date=22 March 2016|date=15 October 2012}}</ref><!-- technically the NTI report is 2012, but if thousands of missiles were known to go off high alert in the past 4 years it would've made the news --> While stockpiles have been on the decline following the end of the Cold War, every [[List of states with nuclear weapons|nuclear country]] is currently undergoing modernization of its nuclear arsenal.<ref>{{cite news|last1=Broad|first1=William J|title=U.S. Ramping Up Major Renewal in Nuclear Arms|url=https://www.nytimes.com/2014/09/22/us/us-ramping-up-major-renewal-in-nuclear-arms.html?_r=0|newspaper=New York Times|access-date=24 January 2016|date=2014-09-21}}</ref><ref>{{cite news|author1=Mecklin, John|title=Disarm and Modernize|url=https://foreignpolicy.com/2015/03/24/disarm-and-modernize-nuclear-weapons-warheads/|access-date=22 March 2016|date=4 March 2015}}</ref><ref>{{cite journal|last1=Kristensen|first1=H. M.|last2=Norris|first2=R. S.|title=Slowing nuclear weapon reductions and endless nuclear weapon modernizations: A challenge to the NPT|journal=Bulletin of the Atomic Scientists|date=20 June 2014|volume=70|issue=4|pages=94–107|doi=10.1177/0096340214540062|bibcode=2014BuAtS..70d..94K|s2cid=145122829}}</ref> The ''Bulletin'' advanced their symbolic [[Doomsday Clock]] in 2015, citing among other factors "a nuclear arms race resulting from modernization of huge arsenals".<ref>{{cite news |last1=Rhodan |first1=Maya |title=4 Times the World Came Close to 'Doomsday' |url=https://time.com/4193889/doomsday-clock-changed-2016/ |access-date=24 May 2020 |magazine=Time |date=January 2016 |language=en}}</ref> In January 2020, it was moved forward to 100 seconds before midnight.<ref name=james>{{cite web | last=James | first=Sara | title='If there's ever a time to wake up, it's now': Doomsday Clock moves 20-seconds closer to midnight | website=ABC News |publisher =Australian Broadcasting Corporation | url=https://www.abc.net.au/news/2020-01-24/doomsday-clock-moves-closest-to-midnight-in-73-year-history/11896294 | access-date=January 24, 2020|date=January 24, 2020}}</ref> In 2023, it was moved forward to 90 seconds before midnight.

[[John F. Kennedy]] estimated the probability of the [[Cuban Missile Crisis]] escalating to nuclear conflict as between 33% and 50%.<ref>{{cite journal |last=Allison |first=Graham |year=2012 |title=The Cuban Missile Crisis at 50 |url=http://www.foreignaffairs.com/articles/137679/graham-allison/the-cuban-missile-crisis-at-50 |journal=[[Foreign Affairs]] |volume=91 |issue=4 |access-date=9 July 2012}}</ref><ref>{{cite web|url=http://www.vzglyad.ru/opinions/2013/11/22/660828.html|title=ВЗГЛЯД / "США и Россия: кризис 1962–го"|publisher=vzglyad.ru|date=22 November 2013|access-date=29 January 2016|archive-date=14 December 2013|archive-url=https://web.archive.org/web/20131214084315/http://www.vzglyad.ru/opinions/2013/11/22/660828.html|url-status=dead}}</ref>

In a poll of experts at the Global Catastrophic Risk Conference in Oxford (17–20 July 2008), the [[Future of Humanity Institute]] estimated the probability of complete human extinction by nuclear weapons at 1% within the century, the probability of 1 billion dead at 10% and the probability of 1 million dead at 30%.<ref>{{cite web|url=http://www.global-catastrophic-risks.com/docs/2008-1.pdf|title=Global Catastrophic Risks Survey|last2=Bostrom|first2=Nick|website=Future of Humanity Institute|publisher=Future of Humanity Institute, Oxford University|last1=Sandberg|first1=Anders|access-date=18 August 2016|archive-date=20 October 2016|archive-url=https://web.archive.org/web/20161020075724/http://www.global-catastrophic-risks.com/docs/2008-1.pdf|url-status=dead}}</ref> These results reflect the median opinions of a group of experts, rather than a probabilistic model; the actual values may be much lower or higher.

Scientists have argued that even a small-scale nuclear war between two countries, such as India and Pakistan, could have devastating global consequences and such local conflicts are more likely than full-scale nuclear war.<ref name="RobockRegional2007">{{cite journal|last1=Robock|first1=A|last2=Oman|first2=L|last3=Stenchikov|first3=GL|last4=Toon|first4=OB|last5=Bardeen|first5=C|last6=Turco|first6=RP|title=Climatic consequences of regional nuclear conflicts|journal=Atmos. Chem. Phys.|date=2007|volume=7|issue=8|pages=2003–2012|doi=10.5194/acp-7-2003-2007|bibcode=2007ACP.....7.2003R|url=https://hal.archives-ouvertes.fr/hal-00296198/file/acp-7-2003-2007.pdf|doi-access=free}}</ref><ref name="ToonandRobock2010">{{cite journal|last1=Robock|first1=A|last2=Toon|first2=OB|title=Local nuclear war, global suffering|journal=Scientific American|date=2010|volume=302|issue=1|pages=74–81|url=http://academic.evergreen.edu/z/zita/articles/SciAm/GW_CC/NuclearWar2010.pdf|access-date=13 February 2016|doi=10.1038/scientificamerican0110-74|doi-broken-date=2024-04-04|pmid=20063639|bibcode=2010SciAm.302a..74R|archive-date=15 December 2017|archive-url=https://web.archive.org/web/20171215060319/http://academic.evergreen.edu/z/zita/articles/SciAm/GW_CC/NuclearWar2010.pdf|url-status=dead}}</ref><ref name="NatureFood2022">{{cite journal |title=Global food insecurity and famine from reduced crop, marine fishery and livestock production due to climate disruption from nuclear war soot injection |journal=[[Nature Food]] |date=15 August 2022 |doi=10.1038/s43016-022-00573-0 |last1=Xia |first1=Lili |last2=Robock |first2=Alan |last3=Scherrer |first3=Kim |last4=Harrison |first4=Cheryl S. |last5=Bodirsky |first5=Benjamin Leon |last6=Weindl |first6=Isabelle |last7=Jägermeyr |first7=Jonas |last8=Bardeen |first8=Charles G. |last9=Toon |first9=Owen B. |last10=Heneghan |first10=Ryan |volume=3 |issue=8 |pages=586–596 |pmid=37118594 |s2cid=251601831 |doi-access=free |hdl=11250/3039288 |hdl-access=free }}</ref>