The Very, Very Useful Kennedys
That may well be true; if one thing is obvious, it's that neither Barack nor Michelle Obama intend to be steamrolled by the Bill and Hillary team. That being said, I have another theory about why the Kennedy family may be emphasized so much over the next few days by a candidate who has tried to embody "change" and "the future" -- even though the family's relevance is primarily in the past.
Remember how, at one point, Barack was using all kinds of presidential props -- a faux seal, a press conference held in East Room style? At the time, I argued that this was a deliberate effort on the part of his campaign to help people "see" Barack as President. My sense is that he and/or many people around him believe that the (bigoted?) American public can't "visualize" a President who "doesn't look like all those other guys on the dollar bills," as the candidate put it. Hence, the stagecraft designed to help.
And now it's family time. Similarly, I'll bet that some around the Obamas think (unfairly, in my view) that many Americans are concerned about what it would "be like" to have an African American family in The White House. So they'll give them the answer: Like the 21st century version of John and Jacqueline Kennedy! They've even got young kids! And Michelle's fashion sense evokes a modern Jackie O! Nothin' to worry about here, rednecks!
And frankly, on that front, there isn't. In The White House, no doubt most of America will conclude that the Obamas would conduct themselves no differently than any other far left young academic/professional couple of whatever color. Most of America isn't fixated on the Obamas' race.
But I don't think they believe that. And lots of Kennedys around help to alleviate the issues that the Obamas seem to believe that voters have.