John Kerry

(OK, not a 4th challenge, just a specific detail to add to Mass' #3 above ): A specific challenge for Sec. Kerry will be working with Susan Rice as National Security Advisor (= the Prediction of the Day from the Chattering Class, and actually predictable from the moment that JK was nominated as SoS).

Reassuring to reflect, though, that Sen. Kerry is a seasoned veteran of this kind of Internecine Stuff (if he can handle 40-odd years of incestuous and highly personal MA politics and emerge victorious, he can handle anything); that (judging from his earlier generous statements) he's almost surely anticipated this scenario (yes, he would have been generous to her anyway, because that's who he is, but his generosity also happened to be a savvy political move); and that, I suspect and hope, he and Chuck Hagel will work in synch with each other as a synergistic, effective team to counterbalance more hawkish folks like Rice.

Kind of OT, but I watched Primary Colors on TV this weekend; as I watched that movie (I also had read the book some years ago), I was impressed once again how that book/movie just nailed the Clintons. And it reminded me once again what a rare treasure Secretary Kerry is: a survivor of 40 years of politics, with his integrity, principles , idealism , patriotism still intact.
Bravo, Secretary Kerry. Thanks for all you have done, and are continuing to do, to make this a better country and a better world.