Can I ask why it is so terrible to offer them coverage? If an illegal immigrant gets injured or deathly ill, they will be taken to an emergency room and treated at taxpayer expense anyway. There are many diseases that can be spread through a sneeze or a cough. Viruses and bacteria do not ask you for papers before infecting you. Heaven forbid an epidemic occurs in America. Don't you think having an underground population with no access to medical care would be disastrous should -- say a Swine Flu outbreak occur? Again, remember that viruses don't ask for immigration documents.
Given that even the public plan is intended to be self-sufficient, paid for by the premiums the users pay into the system, why not let undocumented immigrants pay into the public plan to get coverage, too?
Don't tell me. I already have an idea as to why.