People often seem to forget that the role of the NSA is twofold. As we all know they try to intercept communications to glean intelligence from them (i.e. comprimising communication/encryption systems of other countries). The fact that they do that has never been a secret (since its existence became public knowledge of course ).

The second role that NSA fills is to help secure information systems within the U.S. This is the role that most people seem to forget about. My understanding of these keys was that when the NSA looked at windows for use in some aspects of its work, they decided that the encryption provided by microsoft wasn't up to their standards (also not a surpise). They therefor wanted these keys as a method of implementing a higher level of encryption to make the system more secure, not as a backdoor to make it less secure.

Long story short, yes the NSA is part of the U.S. intelligence effort and as such tries to spy on people; but their job is also to help protect the U.S. from beind spied on by others.

just my $0.02