Is the Health Care Law Unconstitutional? - Say what you want about the Health Care Bill as a whole, but it's important to understand why the requirement for mandatory insurance is included, and why just that particular portion of the bill can't be overturned:
Jack M. Balkin, a Law Professor at Yale explains:
"The new law keeps insurance companies from denying coverage because of preexisting conditions or from imposing lifetime caps on coverage. The individual mandate makes these popular aspects of health care reform possible.
Without an individual mandate people will wait until they become sick to buy health insurance, raising insurance premiums for others and undermining the ability to spread risk that is necessary for private insurance markets. Requiring people to make a choice between buying health insurance or paying a tax gives people incentives to act responsibly and not attempt to game the system."
Other experts have good arguments on the other side too. I always love the NYTimes "Room for Debate" series. Significantly more civil than anything you see on television.