Health care mandates and the Founding Fathers

From an essay in The New Republic:

In making the legal case against Obamacare’s individual mandate, challengers have argued that the framers of our Constitution would certainly have found such a measure to be unconstitutional. Never mind that nothing in the text or history of the Constitution’s Commerce Clause indicates that Congress cannot mandate commercial purchases...

The founding fathers, it turns out, passed several mandates of their own. In 1790, the very first Congress—which incidentally included 20 framers—passed a law that included a mandate: namely, a requirement that ship owners buy medical insurance for their seamen. This law was then signed by another framer: President George Washington...

That’s not all. In 1792, a Congress with 17 framers passed another statute that required all able-bodied men to buy firearms. Yes, we used to have not only a right to bear arms, but a federal duty to buy them. Four framers voted against this bill, but the others did not, and it was also signed by Washington. Some tried to repeal this gun purchase mandate on the grounds it was too onerous, but only one framer voted to repeal it.

More at the link, although I think I've seen discussion elsewhere that the latter mandate was for all able-bodied men to have firearms, not necessarily to buy them.