Hvor konspirationsteorier tidligere mest florerede i små, marginale kredse, blev de i årtierne omkring 2000 til et udbredt kulturelt fænomen i [[massemedie]]r og på [[sociale medier]].{{sfn|Barkun|2003|p=58}}<ref name="Camp 1997">{{Cite book|title=Selling Fear: Conspiracy Theories and End-Times Paranoia|author=Camp, Gregory S.|publisher=Commish Walsh|year=1997|asin=B000J0N8NC}}</ref><ref name="Goldberg 2001">{{Cite book|url=https://archive.org/details/enemieswithincul00gold_0|title=Enemies Within: The Culture of Conspiracy in Modern America|author=Goldberg, Robert Alan|publisher=Yale University Press|year=2001|isbn=978-0-300-09000-0|access-date=6. august 2019|archive-url=https://web.archive.org/web/20191217045836/https://archive.org/details/enemieswithincul00gold_0|archive-date=17. december 2019|url-status=live}}</ref><ref name="Fenster 2008">{{Cite book|title=Conspiracy Theories: Secrecy and Power in American Culture|url=https://archive.org/details/conspir_fen_2008_00_4012|author=Fenster, Mark|publisher=University of Minnesota Press; 2nd edition|year=2008|isbn=978-0-8166-5494-9}}</ref> Det er fremført, at denne tids omsiggribende følelse af [[ensomhed]] har medvirket hertil.<ref>Mads Zacho Teglskov: ''Ensomhed er det 21. århundredes dominerende følelse, og den truer med at ødelægge vores samfund og gøre os til dårligere mennesker'', interview med den engelske økonom Noreena Hertz, Politiken, 26. juni 2021</ref> Teorierne har tilhængere over hele verden, og nogle steder tror endda et flertal af befolkningen på dem.<ref name="van ProoijenDouglas2018">{{cite journal |last1=van Prooijen |first1=Jan-Willem |last2=Douglas |first2=Karen M. |title=Belief in conspiracy theories: Basic principles of an emerging research domain |journal=European Journal of Social Psychology |volume=48 |issue=7 |year=2018 |pages=897–908 |issn=0046-2772 |doi=10.1002/ejsp.2530|pmid=30555188 |pmc=6282974 }}</ref><ref name="SunsteinVermeule2009">{{cite journal|last1=Sunstein |first1=Cass R. |last2=Vermeule |first2=Adrian |title=Conspiracy Theories: Causes and Cures |journal=Journal of Political Philosophy |volume=17 |issue=2 |year=2009 |pages=202–227 |issn=0963-8016 |doi=10.1111/j.1467-9760.2008.00325.x}}</ref><ref name="Brotherton2015-i">{{cite book |author=Robert Brotherton |title=Suspicious Minds: Why We Believe Conspiracy Theories |chapter=Introduction |url=https://books.google.com/books?id=awrcCQAAQBAJ |date=19. november 2015 |publisher=Bloomsbury Publishing |isbn=978-1-4729-1564-1}}</ref>
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