Supporters of the 2010 US Health Care bill: How do you defend the fine imposed for those who remain uninsured?

I will start out by saying that, as far as I know, I fully support the Health Care reform that is taking place. I understand and agree with most of the main provisions, as far as I know.

What I want to know is how you defend the part that concerns those who remain uninsured after 2014 (I believe). Unless they meet a low-income requirement, these individuals will incur an IRS fine of $750 or 2% of their income, whichever is greater. How do you defend that? What do you say to those who wish to remain uninsured? Especially since America is touted as a “free country,” how do you defend this act as not infringing on people’s freedom?