27:
1124:
357:(SAC) was ordered to DEFCON 2, while the rest of the U.S. Armed Forces remained at DEFCON 3. SAC remained at DEFCON 2 until November 15. While at DEFCON 2, 92.5% of SAC's weapons systems (approx. 1,479 strike aircraft; 182 Atlas, Titan, and Minuteman missiles; 2,962 total nuclear weapons; and 1,003 refueling tankers) were ready to launch within one hour, while its
324:. The initial DEFCON system had "Alpha" and "Bravo" conditions (under DEFCON 3) and Charlie/Delta under DEFCON 4, plus an "Emergency" level higher than DEFCON 1 with two conditions: "Defense Emergency" and the highest, "Air Defense Emergency" ("Hot Box" and "Big Noise" for exercises).
319:
informed NORAD "that Canada and the U.S. had signed an agreement on increasing the operational readiness of NORAD forces during periods of international tension." After the agreement became effective on
October 2, 1959, the JCS defined a system with DEFCONs in November 1959 for the
61:. It prescribes five graduated levels of readiness (or states of alert) for the U.S. military. It increases in severity from DEFCON 5 (least severe) to DEFCON 1 (most severe) to match varying military situations, with DEFCON 1 signaling the impending outbreak of
314:
was created, the command used different readiness levels (Normal, Increased, Maximum) subdivided into eight conditions, e.g., the "Maximum
Readiness" level had two conditions "Air Defense Readiness" and "Air Defense Emergency". In October 1959, the
401:
reports indicating that the Soviet Union had sent a ship to Egypt carrying nuclear weapons along with two other amphibious vessels. Soviet troops never landed and the declassified documents did not disclose the fate of the ship and its cargo.
175:
Although a higher DEFCON number refers to a more relaxed defence posture, the term has been misused in popular culture in which "DEFCON 5" is incorrectly used to describe an active conflict situation (such as in the title of the
882:
708:
949:
814:
1099:
936:
361:
expanded to include 1/8th of SAC's bomber forces, allowing an average of 65 planes in the air in position to be directed at targets in the Soviet Union at any given time.
838:
997:
197:
uses exercise terms when referring to the DEFCON levels during exercises. This is to prevent confusing exercise commands with actual operational commands.
875:
667:
447:
ordered the DEFCON level be increased to 3, and also a stand-by for a possible increase to DEFCON 2. It was lowered to DEFCON 4 on
September 14.
1091:
169:
806:
1036:
479:
311:
201:
615:
204:"proposed the adoption of the readiness conditions of the JCS system", and information about the levels was declassified in 2006:
1059:
736:
1030:
427:
on August 18, 1976, readiness levels for US forces in South Korea were increased to DEFCON 3, where they remained throughout
93:
914:
849:
993:
518:
498:
405:
Over the following days, the various forces reverted to normal status with the Sixth Fleet standing down on
November 17.
194:
1144:
786:
489:
89:
528:
165:
378:. The United States became concerned that the Soviet Union might intervene, and on October 25, US forces, including
484:
157:
383:
85:
742:. United States Army Corps of Engineers Savannah District (CESAS) Plan 500-1-12. 1 August 2001. Archived from
133:, as of 2022, the U.S. DEFCON level has never been more severe than DEFCON 3. The DEFCON 2 levels in the 1962
100:; each level defines specific security, activation and response scenarios for the personnel in question.
398:
647:
420:
181:
149:
129:
127:) and different bases or command groups can be activated at different defense conditions. According to
47:
548:
391:
350:
321:
58:
975:
327:
The United States has never declared a readiness condition of DEFCON 1 to prepare for nuclear war.
1128:
112:
20:
976:"Strategic Air Command Operations in the Cuban Crisis of 1962 (Historical Study No. 90 Vol. 1)"
675:
1022:
Words of
Intelligence: An Intelligence Professional's Lexicon for Domestic and Foreign Threats
1020:
428:
414:
379:
358:
354:
142:
54:
761:
590:
193:
Defense readiness conditions vary between many commands and have changed over time, and the
440:
346:
185:), or more figuratively, to describe an aggravated state of mind ("going to DEFCON five").
134:
8:
543:
97:
50:. For security reasons, the US military does not announce a DEFCON level to the public.
700:
692:
622:
494:
374:
On
October 6, 1973, Egypt and Syria launched a joint attack on Israel resulting in the
108:
104:
1066:
1026:
704:
641:
316:
148:
DEFCONs should not be confused with similar systems used by the US military, such as
116:
981:. US Strategic Air Command, via the National Security Archive. pp. 58, 66, 97.
743:
684:
503:
463:
397:
According to documents declassified in 2016, the move to DEFCON 3 was motivated by
387:
124:
120:
444:
62:
906:
160:(INFOCON) and its future replacement Cyber Operations Condition (CYBERCON), and
468:
375:
839:"Emergency Action Procedures of the Joint Chiefs of Staff, Volume I - General"
1138:
944:
937:"The Cuban Missile Crisis: A Nuclear Order of Battle October/November 1962"
722:
533:
43:
1065:. Carlisle Barracks, Pennsylvania: U.S. Army War College. Archived from
928:
696:
177:
1060:"Negotiating With the North Koreans: The U.S. Experience at Panmunjom"
424:
349:
on
October 16–28, 1962, the U.S. Armed Forces (with the exception of
264:
Increase in force readiness above that required for normal readiness
688:
621:. 12 April 2001 (As Amended Through 19 August 2009). Archived from
616:"Department of Defense Dictionary of Military and Associated Terms"
538:
161:
138:
73:
69:
280:
Increased intelligence watch and strengthened security measures
1123:
994:"CIA reveals its secret briefings to Presidents Nixon and Ford"
523:
473:
457:
251:
Armed forces ready to deploy and engage in less than six hours
153:
476:– Hurricane Condition threat rating (military-developed scale)
68:
DEFCONs are a subsystem of a series of "Alert
Conditions", or
26:
807:"Chairman of the Joint Chiefs of Staff Instruction 6510.01F"
787:"From DEFCON 5 to DEFCON 1: understanding the DEFCON levels"
1092:"Complete 911 Timeline: Donald Rumsfeld's Actions on 9/11"
973:
353:(USAREUR)) were ordered to DEFCON 3. On October 24,
16:
Alert posture used by the United States Armed Forces
876:
NORAD/CONAD Historical
Summary: July -December 1959
506:– Similar British system used for terrorism threats
103:Different branches of the U.S. Armed Forces (i.e.
1136:
84:The DEFCON level is controlled primarily by the
588:
848:. April 24, 1981. pp. 4–7. Archived from
497:– Unofficial disaster recovery metric used by
330:
232:Nuclear war is imminent or has already begun
784:
1012:
584:
899:
582:
580:
578:
576:
574:
572:
570:
568:
566:
564:
480:National Command Authority (United States)
460:– Continuity of government readiness level
267:Air Force ready to mobilize in 15 minutes
870:
868:
866:
864:
862:
833:
831:
610:
608:
408:
59:unified and specified combatant commands
25:
1018:
991:
799:
759:
661:
659:
657:
561:
434:
340:
235:Maximum readiness. Immediate response.
53:The DEFCON system was developed by the
1137:
1057:
935:Norris, Robert S. (October 24, 2012).
934:
859:
828:
668:"Nuclear Alerts and Crisis Management"
1039:from the original on 18 November 2015
955:from the original on October 20, 2018
665:
605:
94:Chairman of the Joint Chiefs of Staff
729:
654:
170:U.S. Department of Homeland Security
1000:from the original on 27 August 2016
785:Mickeviciute, Rosita (2023-11-27).
519:United States color-coded war plans
195:United States Department of Defense
13:
490:National Terrorism Advisory System
14:
1156:
1116:
1025:. Scarecrow Press. pp. 93–.
529:Homeland Security Advisory System
369:
166:Homeland Security Advisory System
1122:
485:National Military Command Center
158:Information Operations Condition
1102:from the original on 2021-07-01
1084:
1058:Probst, Reed R. (16 May 1977).
1051:
992:Naftali, Tim (26 August 2016).
985:
967:
917:from the original on 2019-06-28
888:from the original on 2013-09-27
817:from the original on 2022-08-09
760:Theisen, Tiffini (2023-01-24).
714:from the original on 2016-03-04
666:Sagan, Scott D. (Summer 1985).
384:Continental Air Defense Command
974:Strategic Air Command (1963).
778:
753:
737:"Emergency Action Plan (SEAP)"
1:
1019:Goldman, Jan (16 June 2011).
555:
79:
7:
450:
394:, were placed at DEFCON 3.
364:
335:
164:(WATCHCONS), or the former
150:Force Protection Conditions
130:Air & Space/Smithsonian
36:defense readiness condition
10:
1161:
907:"DEFCON DEFense CONdition"
412:
331:Instances of DEFCON 2 or 3
305:
296:Lowest state of readiness
48:United States Armed Forces
18:
1145:Alert measurement systems
549:Preparing for Emergencies
351:United States Army Europe
248:Next step to nuclear war
188:
141:applied only to the U.S.
90:U.S. Secretary of Defense
846:US DoD FOIA Reading Room
589:Tiffini Theisen (2023).
443:, Secretary of Defense
421:the axe murder incident
283:Above normal readiness
21:Defcon (disambiguation)
1096:www.historycommons.org
676:International Security
646:: CS1 maint: others (
359:airborne alert program
31:
429:Operation Paul Bunyan
415:Operation Paul Bunyan
409:Operation Paul Bunyan
380:Strategic Air Command
355:Strategic Air Command
200:On January 12, 1966,
143:Strategic Air Command
72:, which also include
55:Joint Chiefs of Staff
29:
1131:at Wikimedia Commons
855:on January 13, 2014.
441:September 11 attacks
435:September 11 attacks
347:Cuban Missile Crisis
341:Cuban Missile Crisis
210:Readiness condition
154:Readiness Conditions
135:Cuban Missile Crisis
98:Combatant Commanders
74:Emergency Conditions
19:For other uses, see
1072:on October 24, 2005
544:Four-minute warning
628:on 8 November 2009
495:Waffle House Index
32:
1127:Media related to
1032:978-0-8108-7476-3
591:"What is DEFCON?"
512:Historic/Defunct:
322:military commands
303:
302:
299:Normal readiness
117:U.S. Marine Corps
1152:
1126:
1111:
1110:
1108:
1107:
1088:
1082:
1081:
1079:
1077:
1071:
1064:
1055:
1049:
1048:
1046:
1044:
1016:
1010:
1009:
1007:
1005:
989:
983:
982:
980:
971:
965:
964:
962:
960:
954:
941:
932:
926:
925:
923:
922:
903:
897:
896:
894:
893:
887:
880:
872:
857:
856:
854:
843:
835:
826:
825:
823:
822:
803:
797:
796:
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782:
776:
775:
773:
772:
757:
751:
750:
748:
741:
733:
727:
726:
720:
719:
713:
672:
663:
652:
651:
645:
637:
635:
633:
627:
620:
612:
603:
602:
600:
598:
586:
504:UK Threat Levels
464:Combat readiness
388:European Command
207:
206:
162:Watch Conditions
125:U.S. Space Force
121:U.S. Coast Guard
1160:
1159:
1155:
1154:
1153:
1151:
1150:
1149:
1135:
1134:
1119:
1114:
1105:
1103:
1090:
1089:
1085:
1075:
1073:
1069:
1062:
1056:
1052:
1042:
1040:
1033:
1017:
1013:
1003:
1001:
990:
986:
978:
972:
968:
958:
956:
952:
939:
933:
929:
920:
918:
905:
904:
900:
891:
889:
885:
878:
874:
873:
860:
852:
841:
837:
836:
829:
820:
818:
805:
804:
800:
791:
789:
783:
779:
770:
768:
762:"DEFCON Levels"
758:
754:
746:
739:
735:
734:
730:
717:
715:
711:
689:10.2307/2538543
670:
664:
655:
639:
638:
631:
629:
625:
618:
614:
613:
606:
596:
594:
587:
562:
558:
553:
509:
453:
445:Donald Rumsfeld
437:
417:
411:
372:
367:
343:
338:
333:
308:
191:
82:
63:nuclear warfare
24:
17:
12:
11:
5:
1158:
1148:
1147:
1133:
1132:
1118:
1117:External links
1115:
1113:
1112:
1083:
1050:
1031:
1011:
984:
966:
927:
898:
858:
827:
798:
777:
752:
749:on 2013-02-03.
728:
653:
604:
593:. Military.com
559:
557:
554:
552:
551:
546:
541:
536:
531:
526:
521:
515:
508:
507:
501:
492:
487:
482:
477:
471:
469:Doomsday Clock
466:
461:
454:
452:
449:
436:
433:
413:Main article:
410:
407:
376:Yom Kippur War
371:
370:Yom Kippur War
368:
366:
363:
342:
339:
337:
334:
332:
329:
307:
304:
301:
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297:
294:
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285:
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278:
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269:
268:
265:
262:
259:
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252:
249:
246:
243:
237:
236:
233:
230:
229:COCKED PISTOL
227:
221:
220:
217:
214:
213:Exercise term
211:
190:
187:
113:U.S. Air Force
86:U.S. president
81:
78:
15:
9:
6:
4:
3:
2:
1157:
1146:
1143:
1142:
1140:
1130:
1125:
1121:
1120:
1101:
1097:
1093:
1087:
1068:
1061:
1054:
1038:
1034:
1028:
1024:
1023:
1015:
999:
995:
988:
977:
970:
951:
947:
946:
945:Wilson Center
938:
931:
916:
912:
908:
902:
884:
877:
871:
869:
867:
865:
863:
851:
847:
840:
834:
832:
816:
812:
808:
802:
788:
781:
767:
763:
756:
745:
738:
732:
724:
710:
706:
702:
698:
694:
690:
686:
683:(4): 99–139.
682:
678:
677:
669:
662:
660:
658:
649:
643:
624:
617:
611:
609:
592:
585:
583:
581:
579:
577:
575:
573:
571:
569:
567:
565:
560:
550:
547:
545:
542:
540:
537:
535:
532:
530:
527:
525:
522:
520:
517:
516:
514:
513:
505:
502:
500:
496:
493:
491:
488:
486:
483:
481:
478:
475:
472:
470:
467:
465:
462:
459:
456:
455:
448:
446:
442:
432:
430:
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406:
403:
400:
395:
393:
389:
385:
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377:
362:
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328:
325:
323:
318:
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136:
132:
131:
126:
122:
118:
114:
110:
106:
101:
99:
95:
91:
87:
77:
76:(EMERGCONs).
75:
71:
66:
64:
60:
56:
51:
49:
45:
41:
37:
30:DEFCON levels
28:
22:
1104:. Retrieved
1095:
1086:
1074:. Retrieved
1067:the original
1053:
1041:. Retrieved
1021:
1014:
1002:. Retrieved
987:
969:
957:. Retrieved
943:
930:
919:. Retrieved
910:
901:
890:. Retrieved
850:the original
845:
819:. Retrieved
810:
801:
790:. Retrieved
780:
769:. Retrieved
766:Military.com
765:
755:
744:the original
731:
723:Project MUSE
721:– via
716:. Retrieved
680:
674:
630:. Retrieved
623:the original
595:. Retrieved
534:BIKINI state
511:
510:
438:
418:
404:
396:
373:
344:
326:
317:JCS Chairman
309:
288:
277:DOUBLE TAKE
272:
261:ROUND HOUSE
256:
240:
224:
216:Description
199:
192:
180:
174:
168:used by the
147:
128:
102:
92:through the
83:
67:
52:
46:used by the
39:
35:
33:
1076:17 December
959:February 8,
597:19 November
439:During the
392:Sixth Fleet
345:During the
156:(REDCONS),
44:alert state
1106:2016-08-02
921:2016-03-06
892:2013-09-25
881:(Report).
821:2017-05-04
792:2024-04-14
771:2024-04-14
718:2013-05-04
632:1 February
556:References
419:Following
245:FAST PACE
219:Readiness
178:video game
152:(FPCONS),
80:Definition
57:(JCS) and
1004:26 August
705:154595250
425:Panmunjom
293:FADE OUT
137:and 1991
109:U.S. Navy
105:U.S. Army
1139:Category
1100:Archived
1037:Archived
998:Archived
950:Archived
915:Archived
883:Archived
815:Archived
709:Archived
642:cite web
539:CONELRAD
451:See also
390:and the
365:DEFCON 3
336:DEFCON 2
289:DEFCON 5
273:DEFCON 4
257:DEFCON 3
241:DEFCON 2
225:DEFCON 1
182:Defcon 5
139:Gulf War
96:and the
88:and the
70:LERTCONs
42:) is an
1043:6 March
996:. CNN.
911:fas.org
811:jcs.mil
697:2538543
306:History
145:(SAC).
1129:DEFCON
1029:
703:
695:
524:HANDEL
474:HURCON
458:COGCON
310:After
189:Levels
40:DEFCON
1070:(PDF)
1063:(PDF)
979:(PDF)
953:(PDF)
940:(PDF)
886:(PDF)
879:(PDF)
853:(PDF)
842:(PDF)
747:(PDF)
740:(PDF)
712:(PDF)
701:S2CID
693:JSTOR
671:(PDF)
626:(PDF)
619:(PDF)
312:NORAD
202:NORAD
1078:2009
1045:2016
1027:ISBN
1006:2016
961:2022
648:link
634:2014
599:2023
499:FEMA
34:The
685:doi
423:at
399:CIA
1141::
1098:.
1094:.
1035:.
948:.
942:.
913:.
909:.
861:^
844:.
830:^
813:.
809:.
764:.
707:.
699:.
691:.
679:.
673:.
656:^
644:}}
640:{{
607:^
563:^
431:.
386:,
382:,
172:.
123:,
119:,
115:,
111:,
107:,
65:.
1109:.
1080:.
1047:.
1008:.
963:.
924:.
895:.
824:.
795:.
774:.
725:.
687::
681:9
650:)
636:.
601:.
38:(
23:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
