I gave you a hint, Stuart. Research the NFA, 1934. Come on, shooter, look at that law. It's only 83 years old, in my country's history.
You know everything about Australia's gun laws? You're close, proximity-wise. Shiit, I don't. Don't care. Doesn't affect me. I don't know much about Canadian gun laws either, and they're even closer to me. Doesn't affect me, but the more I read and learn, the more those Canuck laws boggle my mind.
You're not expected to know about US laws, but with them being 83 years old now, don't expect us to give you answers on why they make sense, or not. Look into the GCA, 1968 while you're at it. Research some of Bill Clinton's genius, too, from 1994. Shiit, research CALIFORNIA gun laws...