First time requirement of purchase
I've received several emails pointing out that, with regard to statements that the current health care bill is the first to require citizens to purchase something, the 1792 Militia Act required every male of military age to have a musket and ammunition, which was roughly equivalent. So indeed it is not unprecedented, altho most of its backers would not want to invoke requirement that every male of military age prove they had at least one gun!
UPDATE: one of the comments states that Prof. Saul Cornell wrote that the Militia Act was abandoned, on a date two years before it was passed. I didn't recall reading this anywhere, contacted him, and he doesn't recall having written it, either, and thinks it likely that someone else is being confused with him. Could the commenter take a second look and see what it was?