Which level of classified information can be sent through USPS mail?

The classification level of "Confidential" pertains to information that, if disclosed without authorization, could reasonably be expected to cause damage to national security. Information at this level can be sent through USPS mail, provided that appropriate safeguards and procedures are followed to protect it during transit.

The handling of classified information is governed by stringent regulations to ensure its security. For example, while "Top Secret" and "Secret" information can also be transmitted, they have more severe handling requirements and often require specific courier services or secure methods of communication, which typically exceed the capabilities of standard USPS mail.

Unclassified information, while it can be freely sent through USPS, does not require the same security precautions as classified information. However, "Confidential" materials, under the appropriate measures, allow for mail transmission, which differentiates it from the higher levels of classification that necessitate enhanced security measures.

Understanding these distinctions reinforces the importance of handling classified information according to its classification level, ensuring compliance with DoD policies and safeguarding national security interests.