I’ve always thought the National Firearms Act of 1934 was a strange beast. It seemed to be a mishmash of somewhat unrelated items, a grab bag of political expediency. Thanks to David Hardy, it’s a little clearer why that is.
“The big push was to be for national handgun registration. The original form of the NFA 1934 had taxed and thus registered not only full autos and short barrels, but also pistols. Congress took pistols out…”
The NFA makes more sense once you know that it was intended to register and tax everything except standard rifles and shotguns. (I use “more sense” in the logical construction meaning, not in the “sensible gun control” meaning.)
In that light, I think Heller challenges of the NFA may be more viable than I thought since the NFA was clearly an attempt to effectively ban entire classes of firearms including pistols.