R 052131Z NOV 24 MARADMIN 538/24 MSGID/GENADMIN/CMC DCI WASHINGTON DC// SUBJ/PROTECTION OF CLASSIFIED NATIONAL SECURITY INFORMATION// REF A/DOC/UNDERSECRETARY OF DEFENSE FOR INTELLIGENCE AND SECURITY MEMORANDUM/22OCT24// REF B/DOC/SECRETARY OF DEFENSE MEMORANDUM/14APR24// REF C/DOC/SECRETARY OF DEFENSE MEMORANDUM/17APR24// REF D/DOC/SECRETARY OF DEFENSE MEMORANDUM/20JUN23// REF E/DOC/DODD 5200.43 CH3/14JUL2020// NARR/REF A IS THE UNDERSECRETARY OF DEFENSE FOR INTELLIGENCE AND  SECURITY MEMORANDUM ON DEPARTMENT OF DEFENSE SECURITY EXPECTATIONS. REF B IS THE SECRETARY OF DEFENSE MEMORANDUM DIRECTING A REVIEW OF  DEPARTMENT OF DEFENSE SECURITY POLICIES AND PROCEDURES. REF C IS THE SECRETARY OF DEFENSE MEMORANDUM DIRECTING THE IMMEDIATE REVIEW AND  ASSESSMENT OF DEPARTMENT OF DEFENSE INFORMATION SECURITY PROCEDURES. REF D IS THE SECRETARY OF DEFENSE MEMORANDUM ON SECURITY REVIEW  FOLLOW-ON ACTIONS. REF E IS DEPARTMENT OF DEFENSE DIRECTIVE 5200.43 CHANGE 1 MANAGEMENT OF THE DEFENSE SECURITY ENTERPRISE.// POC-DC I/S. A.  SIMPSON/GS-15/SECURITY DIRECTOR, DC I/703-692-0455/ [email protected]// POC-DC I/C. R. BAER/GS-15/USMC SPECIAL SECURITY OFFICER, DC I/ 703-693-6005/[email protected]// GENTEXT/REMARKS /1.  Purpose. To emphasize the importance of  protecting classified national security information (CNSI) as a  critical aspect of unit and mission readiness. 2.  Background. In the wake of a highly publicized unauthorized  disclosure of CNSI, the Secretary of Defense, via references A  through D, directed a department-wide review of security programs,  policies, and procedures to identify needed improvements to prevent the unauthorized disclosure (UD) of CNSI.  The Marine Corps has  completed its assessment and is implementing the necessary  improvements to reduce the risk to missions, personnel, information and infrastructure from the improper handling or UD of CNSI.   2.a.  Protecting CNSI is an all-hands responsibility that  encompasses leaders and supervisors at all echelons as well as the  individual Marines, Sailors and Civilian Marines who have access to CNSI. 2.b.  It is Marine Corps policy to prioritize the security of CNSI  as a critical aspect of unit and mission readiness.   3.  Execution. Marine leaders will regularly emphasize the  importance of practicing all aspects of security including  cybersecurity, operations and physical security, information  security, personnel security and insider threat programs as it pertains to safeguarding CNSI.  Annual online security training is a valuable tool, but it is not a substitute for engaged leadership.   Marine leaders are the key to inculcating a security-minded command  culture by periodically addressing the risks to unit readiness from  improperly handling CNSI  the same way safety is always emphasized  prior to conducting live-fire training or before a long weekend.   4.  Thank you for your leadership on this matter and for your  continued diligence to improve and enhance the Marine Corps  security posture. 5.  Release authorized by LtGen M. G. Carter, Headquarters Marine  Corps, Deputy Commandant for Information.//