Today, the only recognized limitations are that (1) Congress may not regulate non-economic behavior based solely on an attenuated link to interstate commerce, and (2) Congress may not regulate intrastate economic behavior if its aggregate impact on interstate commerce is negligible.

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The individual intrastate farmer is performing an economic activity that has a connection to interstate commerce.

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Congress can regulate even purely local, intrastate economic behavior so long as, in the aggregate, it substantially affects interstate commerce.

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Perversely, the individual mandate compels individuals by law to purchase health insurance sold only within completely intrastate markets, a regulatory compulsion that by its very construction fails to involve the regulation of interstate commerce, which presumably authorizes it in the first instance.

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