One would wonder why a 'rational' person or group would oppose closing the gun show loophole or requiring stricter standards for registration. (Opposing banning sales of a product from which they profit, like assault weapons, is completely understandable).
The most logical explanation is that the NRA, being primarily a gun manufacturer's organization, REALLY opposes any changes which will result in accurate statistical data about US gun owners. If indeed a perfect statistical base existed, I suspect that there would be a huge discrepancy between ACTUAL gun ownership by US citizens and numbers of guns manufactured (for which there is very good data).
So if not all guns manufactured here are actually sold here, where are they sold? Criminals? Gangs? Gunrunners? Restricted groups?. And of course any knowledge of such activity would eventually result in actions costing gun manufacturers up to 30% of their current sales/profits.
As long as no one knows, no one cares. Obfuscation=Profit. So don't act puzzled when the NRA opposes what all rational people consider 'no-brainers' and logical common sense solutions.
Here's a question: Would the NRA support a law allowing individuals to manufacture their own guns? After all, its our 2nd Amendment right. We need protection. Maybe 20 seconds after that was proposed, the NRA would launch a multi-million dollar campaign against it. Why? Because its all about profit.