What does the marking //CTS-A signify in NATO classification?

The marking //CTS-A signifies "COSMIC TOP SECRET ATOMAL" within NATO classification. This designation is used for the highest level of classified information that involves nuclear-related matters or atomic energy. In NATO's classification system, COSMIC TOP SECRET is the most stringent classification, reserved for information that, if disclosed, could cause "exceptionally grave damage" to NATO’s security interests. The ATOMAL designation indicates that the information specifically relates to atomic or nuclear materials, plans, or capabilities.

Understanding this marking is crucial for personnel who handle sensitive information to ensure that they follow the appropriate protocols for access, sharing, and protection against unauthorized disclosure.