INAL but I'm pretty sure that all that national security issues would mean is that the retained records must be kept classified for the duration relevant to their security classification. It doesnt mean that they can destroy them to keep the dirt from getting out at some time in the future. Besides, National security is about the security of the country, not maintaining the reputation of some politician that did something wrong and wants to keep it secret. You could argue its against the national interest to keep such things secret, as even if it hurts bush and his administration for things to come out, doesnt it hurt democracy more for them to get away with it? Which is the greater good?