Even Mrs. Clinton thought she needed Senator on her resume.
Mrs. Obama could not possiby unite the Clinton and Obama wings of the party, and does nothing to get the technocrat-left on board.
She would also make a lot of enemies among those who want to have a clean shot at the nomination. There is no evidence that she can talk policy outside of platitudes, nor that she can withstand tactical barbs pointed at her by Trump.
The fact that he is willing to punch back makes him perfect for running against someone like Mrs. Obama. She will also spend a lot of time explaining Mr. Obama’s acts without being able to take credit for them.
She certainly likes being talked about as if she were presidential material, but she isn’t foolish enough to damage the brand name by actually running.
Even Mrs. Clinton thought she needed Senator on her resume.
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At one time, I would have completely agreed with that idea about having some sort of previous office. But in November of ‘16 - that all changed.