Cloud computing will save the U.S. government quite a bit of money and improve its efficiency, no doubt, but until government officials are convinced of its security, the migration to this new computing paradigm is likely to be a slow one. As the delayed deployment of the Los Angeles police department’s new Google (GOOG) email system illustrates, the threat of unknown security risks far outweighs the 25 to 50 percent savings in IT costs that the Brookings Institution claims U.S. agencies can save by moving to cloud computing.

So Google’s announcement Monday that its Apps for Government cloud-based productivity suite had gained certification under the Federal Information Security Management Act was quite a win for the company. In theory, that seal of approval will instill in government a modicum of confidence in the security and reliability of the cloud-computing model.