A reader writes:

Having been bitter opponents in the Primary, there is definitely a perception of rivalry between Clinton and Obama. However, that rivalry is really only on one specific front: politics. I.e. this is not a rivalry based on policy.

Obama's core message is to change the nature of politics in Washington. There simply is no room for compromise on this specific message. Clinton does not feel that the current political system is broken. She only believes that the wrong party is in power. These are not stances on which there can be common ground. And if there were common ground, it would only serve to erode Obama's rationale.

Is there room for Obama to bring in rivals? Of course. But I think those rivals should be picked for policy differences. Picking policy rivals would be the way for Obama to fulfill his central promise in this campaign. Picking purely political rivals would prevent this fulfillment.

But policy rivals suggests incoherence. Maybe Hagel works?