Why Isn't Racial Definition Regulated By The Government?

I've been watching the coverage of the Zimmerman trial, and was struck by something.  Every mainstream media outlet either ignores his race (while showing his picture) or refers to him as white.  Every race baiter who is out there protesting the horrible injustice perpetrated upon poor departed Saint Trayvon refer to Zimmerman as white, and that this is a example of white against black racism. 

I have a question.  Zimmerman is mixed blood, half white and half Hispanic.  Why is he almost never referred to as Hispanic in the reporting?  He designates himself as Hispanic on all government forms.  Why is that ignored?  (Well, we know why - race baiters don't make as much money fueling black vs. Hispanic racism, do they?).

If Zimmerman had been reported as Hispanic when this whole thing began, does anyone in their right mind believe it would be as big a deal as it is?  Would Obama have stuck his nose into it?  Would Holder and his DoJ Brownshirts be overseeing all of it?  Would charges have even been leveled against Zimmerman at all?

Contrast this with our Dear Leader, Mr. Obama.  He is half black and half white.  Indeed, he was raised by his white mother and white grandparents - his black father had almost nothing to do with him.  His black relatives over in Africa don't mean a damn thing to Obama, if his treatment of them is any indication.  So, why does Obama refer to himself as black?  Why does the mainstream media, and pretty much everyone in the world, refer to him as the first black President (Bill Clinton not withstanding)?

Why does Obama choose to identify himself as black, when he by all rights should refer to himself as white?  Obviously, because being black 'works' for him.  Does anyone actually think he'd have been elected to anything, much less President, if he called himself white?

Why is there no standard for this?  Hell, the government wants to control everything, why doesn't it impose some rules on this?  Either say the father's race is the defining one, or the mother's. 

(Well, that doesn't work in today's new reality, does it?  Stupid me.  There could be two mothers, or two fathers, or a father and three goats, two mothers and a horse ....)

Update - Four times in the past few days I have CNN refer to Zimmerman as a 'White Hispanic'.  Why the hell don't they refer to Obama as a 'White African American'?