From the "Command and Control" book:
"Despite the obsolescence of the Titan II, its decommissioning would proceed slowly. The last missile was scheduled to go off alert in 1987. In order to save money, the Air Force decided to cancel some of the modifications recommended by the Titan II review group after the accident in Damascus. Funding would not be provided for a new vapor detection system in the silo, additional video cameras within the complex, or a retrofit of the W-53 warhead with new safety mechanisms. Upgrading the warhead to meet “modern nuclear safety criteria for abnormal environments” would have cost about $400,000 per missile."
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