The database that's exists is actually many smaller databases from agencies that do not share information easily. This failure of interoperability is the elephant in the room that must be overcome in order to have a chance at providing some measure of safety for American Citizens. For example video footage of the cash register at Walmart and local pawn shops should be one source linked to facial recognition software. Airport, train, bus, and border crossing footage is another source that should be linked. Certain items sold at hardware stores should be red flagged and enable video footage that should be linked. While this may seem invasive, if it stops one Mc Vey or prevents a Sandy Hook, in my opinion, it will be worth it.