1. A method for interacting with a virtual content repository in a content management system, the method comprising: providing a virtual content repository (VCR) with a plurality of content repositories, wherein the VCR is capable of modeling content in the plurality of content repositories and providing uniform content services; providing, via the VCR, a federal level security mechanism and a repository level security mechanism, wherein the federal level security mechanism is associated with each content repository of the plurality of content repositories and is based on one or more federal level security policies that are defined for differing classes of users that can access content in the VCR, and wherein the repository level security mechanism can be associated with at least a first content repository in the VCR, but not associated with a second content repository in the VCR; receiving, via a common Application Programming Interface (API), a request to access content stored in the VCR; preparing a result set from the VCR responsive to the request after applying the federal level security mechanism, wherein the result set includes content from both the first content repository and the second content repository that satisfy the one or more federal level security policies; applying the repository level security mechanism to the result set, wherein the repository level security mechanism is associated with a repository level security policy; redacting the result set received from the VCR to exclude the portion of the result set that is returned by the first content repository, prior to providing access to content in the result set, when the request does not satisfy the repository level security policy; and providing access to content in the VCR when the request satisfies the repository level security policy.