{{Short description|Concept in nuclear military strategy}}
'''Fail-deadly''' is a concept in nuclear military strategy that encourages deterrence by guaranteeing an immediate, automatic, and overwhelming response to an attack, even if there is no one left to trigger such retaliation.{{Citation needed|date=April 2025}} The term ''fail-deadly'' was coined as a contrast to ''fail-safe''.
Fail-deadly can refer to specific technology components, or the controls system as a whole. The United Kingdom's fail-deadly policies delegate strike authority to submarine commanders in the event of a loss of command (using letters of last resort), ensuring that even when uncoordinated, nuclear retaliation can be carried out.<ref>{{cite book |last=Scott |first=Len |date=2000 |title=Planning Armageddon |url=https://books.google.com/books?id=lWNwZZ1tV_8C&pg=PA301 |location=Amsterdam |publisher=Overseas Publishers Association |isbn=9058230066 |page=301 }}</ref>
==See also== * AN/DRC-8 Emergency Rocket Communications System * {{Annotated link|Dead man's switch}} * {{Annotated link|Doomsday device}} * ''Dr. Strangelove'' * {{Annotated link|Failing badly}} * {{Annotated link|Launch on warning}} * Mutual assured destruction (MAD) * {{Annotated link|Samson Option}} * {{Annotated link|Special Weapons Emergency Separation System}} * Two Generals' Problem * Dead Hand
==References== {{Reflist}} {{Wiktionary}}
Category:Nuclear command and control Category:Nuclear strategy