If the success of a law was measured by 100% adherence, then no law is successful.
Laws against murder are pretty universal and we don't have the NRA fighting against them.
Is your point that we should have neither?
The NRA and many on the far right are actually fighting against gun laws.
Also, I would bet that while neither eliminate the crimes they do actually help reduce the overall member of crimes.
A gun ban will make it harder to own a gun in that area, but it can't address the fact that one can drive to an area where there isn't a gun ban and buy a gun.