So Congress has no authority to require individuals to make a purchase? Really?

Be it enacted by the Senate and House of Representatives of the United States of America, in Congress assembled... That every citizen, so enrolled and notified, shall, within six months thereafter, provide himself with a good musket or firelock, a sufficient bayonet and belt, two spare flints, and a knapsack, a pouch, with a box therein, to contain not less than twenty four cartridges, suited to the bore of his musket or firelock, each cartridge to contain a proper quantity of powder and ball; or with a good rifle, knapsack, shot-pouch, and powder-horn, twenty balls suited to the bore of his rifle, and a quarter of a pound of powder...

Mandating individuals to purchase health insurance, opponents claim, isn’t a regulation of economic activity. According to Virginia Attorney General Ken Cuccinelli, “We contend that if a person decides not to buy health insurance, that person—by definition—is not engaging in commerce and, therefore, is not subject to a federal mandate.”

Yet people who fail to buy health insurance are engaging in economic activity. They are making an economic decision to self-insure. If they fall ill, they usually find that they can’t afford medical care and visit an emergency room. Or they go without care, allow their condition to worsen, and then get taken to an emergency room. In either case, the American people foot the bill. The national economic consequences of individuals deciding to go without insurance are enormous.

Even if self-insuring could be construed as non-economic activity, the individual mandate is still within Congress’s commerce power. The High Court has held on numerous occasions that Congress can regulate non-economic activity as part of a larger, comprehensive effort to regulate some aspect of our national economy. Just a few years ago, the Supreme Court held that Congress, as part of its effort to stamp out interstate commerce in illegal drugs, could prohibit a person from growing marijuana in his own home for his own use. The court has also said that Congress, as part of regulation of wheat prices, can limit the amount of wheat a farmer grows on his own land for his personal use.

With health care, controlling precedent seems to clearly allow Congress, as part of its comprehensive effort to regulate the interstate health-care market, to require individuals to have insurance coverage. Even if the decision to go without insurance is not economic activity, Congress can reach it because health care profoundly affects interstate commerce.

...each and every free able-bodied white male citizen of the respective States, resident therein, who is or shall be of age of eighteen years, and under the age of forty-five years (except as is herein after excepted) shall severally and respectively be enrolled in the militia...

...each and every free able-bodied white male citizen of the respective States, resident therein, who is or shall be of age of eighteen years, and under the age of forty-five years (except as is herein after excepted) shall severally and respectively be enrolled in the militia...

Congress has have the power

...

To provide for calling forth the Militia to execute the Laws of the Union, suppress Insurrections and repel Invasions;

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;

The power to regulate interstate commerce is one of the most important powers of Congress and is the basis for most federal laws, including Medicare, Social Security, drug laws, civil-rights laws, and others. Since the 1930s, the Supreme Court has said that Congress’s commerce power is very broad and can be used to justify regulation of nearly any activity that substantially impacts interstate commerce.

While the SCOTUS may indeed interpret the CC as delegating the power to mandate purchases and regulate "lack of commerce" it is valid to challenge it.

I even said SCOTUS may expand upon previous precedent and say the law is Constitutional but this is what is SUPPOSE to happen. Government at work. Checks and Balances and all that quaint stuff.

I don't presume to speak for the Supreme Court and many who do end up looking foolish.

Many people though the Constitutional challenge in Heller v. DC would lose and it didn't.

The challenge may indeed lose but it has nothing to do with militia act. The commerce clause is broad but not unlimited. Supreme Court has 3 times in last 20 years ruled action taken under Commerce Clause was Unconstitutional.

I never claimed govt lacks the ability I simply stated in remains unsettled law.
Also the militia act "link" is just plain stupid.

If HCR mandate is Constitutional it will be because of power delegated by Commerce Clause (Article I, Section 8, Clause 3).

The precedent is clearly via Commerce Clause and even then courts may rule this is overstepping the bounds. They have done so in the past. The power of Commerce Clause is large (too large IMHO) but it isn't unlimited. It is a question for the courts to see if HCR mandates fall within that broad but unlimited power.