If the government can mandate what you can buy, it surely can mandate what you can't buy.
One day the government may come to my house and tell me to buy a gun and a Bible. Next day the government may come to may house and tell me to buy a Chevy Volt, and a particular brand of condoms. And when you don't buy what the government tells you...
I won't go to the government's camps without bringing death and destruction with me.
5.56mm
We own neither. This will just make it permanent.
There was a time gov't did tell white men of a certain age (18-45) to buy a gun. It was the Militia Act of 1792. Militias are a special case since they're specifically constitutional.