"Obamacare" as Health Insurance Privatization

The Affordable Care Act is often characterized as a massive government program designed to extend health insurance to millions. It might more accurately be characterized, however, as a massive privatization mechanism designed to move millions of individuals from the existing socialist system of de facto public insurance - taxpayer-funded emergency room visits for the technically uninsured - to private insurance coverage. Why aren't conservatives embracing this market-based solution to a problem of socialism?