HOW DOES freedom slip away? It doesn't happen one day, all of a sudden, without warning. It erodes in stages. One day you read that an employer has fired four employees because they refused to follow the company's no smoking policy -- including not smoking in their own homes on their own time -- and that's OK, because you don't smoke. A year or two later, employers go after your pet vice -- eating, tippling, maybe snowboarding -- and then such a policy is an outrage. So Americans should be wary of the news last month that a Michigan health-...