Until recently, the Pentagon has stayed away from social media such as Facebook and Twitter. Pentagon will be moving forward with the use of social networking tools as a communication bridge between the public and the non-classified activities of the agency--as announced in a press release from Feb. 26th 2010 containing the headline "DOD Releases Policy for Responsible and Effective Use of Internet-Based Capabilities". It will also allow the social networking tools to be used within it's Non-Classified Internet Protocol Router Network (NIPRNET)--saying that it found a proper balance between the necessary security criteria and the use of social tools.
The Pentagon recognized that the decision between social networking and security is not a yes/no decision. Although the military has been using social networking for quite some time, it has never been a unified approach across all it's branches.