Five years is a blink of an eye in the gun culture. I was around when the Hughes Amendment passed. It happened so quickly the NRA didn't have a chance to do anything about it.
It had its warts, but several provisions of the FOPA were badly needed. When the Hughes Amendment was slipped in, literally at the 11th hour, it was decided that the overall Act was still worth supporting, as it did the most amount of good for the most people.
I was there when Bush 41 pushed for his import ban in 1989. In fact, I worked a phone bank at the time. I can guarantee that there are people posting here today who yelled at me for interrupting their dinner and hung up on me when I called on their behalf.
The NRA can only do what its membership supports, and if membership have been apathetic and unwilling to participate, then there's only so much that can be done. Nonetheless, the NFA would have applied to handguns if it weren't for the NRA. We would have had a ban, or at least a national New York style registration scheme, on handguns by the mid-1970's.
The EPA and OSHA would have shut down almost all hunting land in the country by now, and ammunition likely would have been regulated to the point of prohibitive expense. It would have been done so quietly that the general public wouldn't have known until it was over.
The Assault Weapons Ban would not have had a sunset provision. Again, I'll bet money there are people here who said, "I don't care about machine guns long as I get to keep my .30-30."
That's just the stuff I can come up with off the top of my head. All of this the NRA did in spite of a large percentage of their membership, who contribute nothing past minimum dues. I'd say that's a pretty efficient and dedicated operation.