Historically when a government is preparing to oppress the shit out of a population, they like to disarm them beforehand. The Romans did it, the English did it, it's happened before, after, and in between.
Thinking "good luck having any effect on your super government with small arms" is an uneducated presumption. Although it is my opinion the 2nd amendment allows for us all to have much more than what is currently accessible, even a comparatively small band of weakly armed insurgents can be effective.