The US military has come up with a cunning way to prevent the leaks of classified documents: it has banned troops from using removable media.

The move appears to be a response to claims by soldier Bradley Manning that he was not only responsible for the leak of both a video of a helicopter attack in Baghdad and the recently published batch of US diplomatic cables, but that he was able to get the documents out simply by writing them to a CD-R that he had labeled as containing Lady Gaga music.

Earlier this year, a Pentagon review suggested that all military computers containing classified information be set-up so that they cannot write to removable media. It’s not known if this measure has been implemented as of yet, though there is now a security system that monitors around 60% of the machines for unusual activity.

The new order bans the use of any removable media on SIPRNet, a collection of networks run by the Department of Defense and Department of State for handling classified material. Millions of people have access to SIPRNet, which frankly makes it amazing that no data was leaked before Manning’s actions.

Removable media was also banned at one point in the past from SIPRNet during a scare over a worm spreading across the network. The new measure appears to be a permanent move.

While some in the military say the change will make their jobs harder (one source told WIRED it is like trying to build a home without a hammer), officials say the ban will be enforced. The memo announcing that change reminds staff that continuing to use removable media would be a direct failure to follow orders and could result in a court-martial.