I’d suggest we are missing quite a lot. NICS stands for National Instant Criminal Background Check System. It is not a data base but sure smells and quacks like one, and if I may say, the building of government lists/databases is not for maintaining the Liberty of the people, but just the opposite. Beware the attempts at legislating every jot and tittle. It does work to make criminals of the law abiding.
I find this on the FBI Web site to be enlightening. NICS is located at the FBIs Criminal Justice Information Services Division in Clarksburg, West Virginia. It provides full service to FFLs in 30 states, five U.S. territories, and the District of Columbia.
Certainly begs the question who are the missing twenty states, and why are they not “invested”. Recent attempts at legislating those deemed mentally unqualified to own or possess a firearm and produce a data base of such, failed on a fluke in a House Committee by one vote. It will surely return next year for another try. This issue is worth much more than a thread will fix or address.