My job does not control me

My job just released a new policy saying that in order to offer any opinion concerning the company, we must offer a disclaimer. We can also be disciplined for complaints or negative feedback. That is, if we identify ourselves as an employee of the company. Sounds a lot like big brother or a dictatorship to me. Not that I would be dumb enough to bash my employer by name for fear of some vindictive asshole in management taking offense, but how does my employment extend to my life outside the walls of my job? Social networking has taken our thoughts and opinions to a whole new stage, but I don't see how any corporate entity is going to dictate to me what I can or cannot post. Not that I really need to whine about my job while I'm home. That would be letting my job get me down and that will not happen. I will deal with being physically tired when I get home, but I won't let myself get mentally down. I learned that one a while ago when I let my job take me over. Not again, and I certainly will not be muzzled by it. Like I stated before, I don't need to nor like to post about my job, but this policy is really taking it too far. No company I work for will ever, ever constrain what I can or can not say or think or type.