Think Progress is alarmed that the coming Constitutional crisis over the President's newly-signed Patient Protection and Affordable Care Act (PPACA). I conclude this because it is unusual to see progressives use an originalist argument for Constitutional interpretation. However Ian Millhiser and Think Progress need more practice at it, because the argument they make is not the one they intend.
I'll start with Millhiser's last point, that the framers "they probably knew a little bit more about the Constitution than Ken Cuccinelli." This is not entirely true for several reasons. First, we've ratified seventeen amendments to the Constitution since the passage of the second Militia Act, and ten more were only ratified six months earlier. These changes to the Constitution require careful consideration, especially those of the ninth and tenth amendments.
Regardless, Millhiser makes one core point: If it is Constitutional to require individuals to purchase firearms in the course of regulating the Militia, then it is Constitutional to require the purchase of medical insurance. However there is a key difference between the two here: the Militia Acts of 1792 are grounded in two specific clauses in the Constitution, while the PPACA has no such support. First see Article 1, Section 8:
The congress shall have the Power [...] To provide for organizing, arming, and disciplining, the Militia, and for governing such Part of them as may be employed in the Service of the United States, reserving to the States respectively, the Appointment of the Officers, and the Authority of training the Militia according to the discipline prescribed by Congress;
We see here that the Constitution expressly allows for the Congress to provide for arming the militia. The second Militia Act does that, among other things. Further, the Second Amendment was passed to ensure all free men could arm themselves with weapons purchased and owned by themselves as individuals, as provided for in the second Militia Act:
A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed.
So if Millhiser can find support for medical insurance regulation with as much plain language as has arming and regulating the Militias of the states, then his point will be better taken. Until then, all he's done is support the individual rights interpretation of the Second Amendment, and possibly given a future administration cover for a military draft. But if he wants to defend the PPACA with this act, he needs more practice reading his Constitution and arguing from it.