Probably pissing in the wind here, but I'll try anyway.
There are many reasonable reasons to not like President Obama's work as president. I certainly hope that no one is shouted down for raising them.(I've certainly raised some myself, and often faced substantive and not so substantive pushback on my arguments.) But I hope there is no room for debate that racist criticisms are completely unacceptable.
While we can sometimes disagree reasonably as to whether a particular critique is imbued with racism, intentional or otherwise, when we see it, I hope we can all condemn it. Of course, responding to substantive critiques with false cries of racism is injurious to discourse and the fight against real racism. But sometimes matters are gray, and in those cases, I personally would err in avoiding a critique that might stray into racialism. It just seems the smart thing to do to me (not to mention the right thing to do.) I'd rather my arguments be addressed on the merits rather than be derailed by a debate about the potential racial nature of what I am saying.
Similarly, critiques of Hillary Clinton are often imbued with sexism, and the Media (as detailed in Susan Gardner's excellent post) has a long history of this.
There are many substantive reasons to oppose Hillary Clinton's potential presidential candidacy in 2016. And I feel confident that they will be debated right here at daily kos in a substantive and illuminating way I hope that Clinton supporters will recognize the validity of debating these points. But I also hope that detractors will recognize that sexism has been a part of the story of the coverage of Hillary Clinton since she emerged on the national stage over 20 years ago.
I hope that we can recognize the malignancy of the racism imbued in some of the attacks on the President and the sexism in some of the attacks on Hillary Clinton, while at the same time recognizing that there are legitimate and substantive points of debate about both of them.
If we can not, it seems to me, it will be difficult to have a real discussion about this over the next 2 years.
My 2 cents.