Yesterday the Royal Australian Navy sang happy birthday to itself by tweet after turning 99 this week, which at least beats describing the mess-hall lunch menu. Several hours later it was back on Twitter after remembering this week was also the Army’s birthday.

The Australian military is catching up with social media like every other major employer. An ADF spokeswoman says it is a “rapidly evolving area” and there is an ongoing review of policy regarding how personnel can use it.

On Friday the US military took a bold step on that front, telling its two million personnel that they’re trusted to blog, poke, tweet and upload YouTube clips at work. The new policy released on Friday covers official and private uses and strikes down bans on more than a dozen social media sites and web 2.0 applications like Gmail on the military’s non-classified computer network.

“I want more, not less” blogging from the front lines, Principal Deputy Assistant Secretary of Defense for Public Affairs Price Floyd said earlier today.

Military family support services told Crikey the bans only hurt deployed personnel and their loved ones, who in an effort to stay connected would buy expensive non-government internet access in Iraq and Afghanistan.

Appropriately enough the new policy was first announced on Twitter — to a supportive audience — and came with a raft of caveats designed to manage risk. Commanders can temporarily cut off access to safeguard operational security or preserve bandwidth, and accessing sites with p-rnography, gambling or hate-crime activities is still punishable.

The rollout includes department-wide training on “proper use” of social media. That education campaign will help stem unauthorised public comment leaking into journalists’ hands and controversial video clips that have enflamed the web.

After a video of a US soldier throwing a puppy off a cliff appeared on video sites in 2008 the Army tried a more liberal policy that emphasised restraint. When the Marine Corps released a contradictory policy banning all social media, the Department of Defense began a seven-month review resulting in the new department-wide rules.

“This directive recognises the importance of balancing appropriate security measures while maximising the capabilities afforded by 21st century internet tools,” said Deputy Secretary of Defense William J. Lynn III.

The US military has a marketing budget slightly larger than the GDP of Sierra Leone, at just under $2 billion, but no largess is quite as effective as social media if you need to get official word out fast. A new register will be created for all official social media channels too, such as the Twitter account of Admiral Mike Mullen, chairman of the Joint Chiefs of Staff. Mullen currently has more than 16,000 followers.

US Navy ships stationed in Hawaii during the tsunami threat alerted the concerned public of their status via tweets and Facebook updates.

This comes as the Obama Administration is pushing US agencies to be more accountable and open to the public through Open Government initiatives. Data.gov now hosts 1077 datasets released during the first 45-day deadline. The Department of Defense has released very little so far, and has begun seeking suggestions through its OpenDefense website, which encourages feedback and voting on ideas.

The Australian Defence Force was a little slower to jump on social media for official use, and still blocks many web 2.0 applications on the Defence Restricted Network. The ADF’s first Facebook page came about not through its Public Affairs directorate, but a suggestion from a young cadet who happened to be working in joint headquarters. Each service now boasts Twitter, Facebook, YouTube and Flickr profiles.

ADF rules for unofficial use of social media show none of the trust the US military has extended. Instead social media is lumped in with the policy governing talking to the media or foreign officials.

“Defence respects the rights of all personnel to exercise freedom of expression, however Defence personnel are not authorised to release official information without clearance,” an ADF spokeswoman told Crikey. Holding back further use is safety, operational security and international relationships that need to be protected.

Last updated in 2007, the policy makes a service member’s commanding officer the judge of whether they are free to upload: “video newsletters, ‘home videos’, and documentaries; publication of information and imagery on the internet, mobile networks and other electronic media, including SMS, email and attachments, ‘blogs’, ‘chat rooms’, podcasts, text messaging and all forms of ‘new media’.”

If that sounds a little out of step with the 17-year-old recruits, the ADF is scheduled to review the policy in October this year.