In response to the Supreme Court ruling, via the individual mandate in the Affordable Care Act, that the federal government can order citizens to purchase goods and/or services even if they don't want to:

No law passed by Congress, nor any ruling of the Supreme Court or any court created by Congress, nor any rule or regulation developed or administered by the federal government, shall be construed as imposing a requirement on an individual or corporation to purchase a particular good or service, nor compel any individual or corporation to purchase a particular good or service, nor impose a tax, fine or penalty on any individual or corporation who fails to purchase a particular good or service.