The repression involved in the implementation of alcohol prohibition had an effect of pushing a common and integral part of society into the black market.
The NRA is promoting the right to bear arms, and actually it would seem that the effect they're seeking should be the exact opposite.
Effectively, as prohibition pushed a polite leisure into the black market. The NRA's goal appears to be the exact opposite: that is, to keep a polite leisure out of the black market.
I don't think German understands the irony of this, because I get the impression that they want to compare the moral status of the prohibition movement to the moral status of the NRA.