Why do we socialize everything but our healthcare?

Our military defense, taxes, voting system, business policy, media regulations, financial system and many other things affecting our very livelihood are all socialized. Why not the healthcare system? I'm upset that a bright young woman I know has to stay in her dead end job so that she can continue to receive healthcare benefits through her union. The fact that we need a union underscores the very problem with the systems we have now. A union shouldn't have to exist to give a hard working person healthcare benefits. It is despicable.