Peggy Noonan reaches a conclusion:
The Democrats’ problem is that most of them know that the person who would emerge, who would challenge Mr. Obama from the left, would never, could never, win the 2012 general election. He’d lose badly and take the party with him. Democratic professionals know the mood of the country. Challenging Mr. Obama from the left would mean definitely losing the presidency, as opposed to probably losing the presidency. There is only one Democrat who could possibly challenge Mr. Obama for the nomination successfully and win the general election, and that is Hillary Clinton. Who insists she doesn’t want to.
Of course, it strikes one that Clintons are almost as famous for their honesty as for their lack of ambition.