The most important thing that Barack Obama did this week — and no, it wasn’t the birth certificate sideshow — was the long-anticipated reshuffle of national security positions, featuring Leon Panetta moving from CIA to Defense and General Petraeus replacing him at CIA. But what’s particularly interesting about the moves he made is what they tell us about the national security dilemmas he faces.

Obama officially announced the selections this afternoon. I was inclined to think the selections were first-rate — I’ve long been a Panetta fan — but I was waiting to hear from Fred Kaplan before commenting, because he’s both a smart observer and because he has excellent sources within the national security establishment. Kaplan is...I don’t think “thrilled” is too strong:

[U]nder the circumstances, it’s hard to imagine a shrewder set of moves, both politically and substantively...Defense right now is] a nightmare job for anyone but Panetta has as much experience as anyone at carving out that sort of territory ... Picking Petraeus to run the CIA is a move worthy of chess masters.

Kaplan correctly identifies the problems facing the Obama Administration: First, downsizing and ending the active military commitments in Iraq, Afghanistan, and Libya without the politically damaging perception of “losing” those conflicts; and second, the prospect of real Pentagon budget cuts.

Presidential scholar Richard Neustadt talked about viable public policy needing to be “manageable to the men who must administer it, acceptable to those who must support it, tolerable to those who must put up with it, in Washington and out.”

Budget cuts mean that there’s going to be a whole lot of “put up with it.” And Panetta, with his vast experience with bureaucratic politics, particularly in the budget realm, should be good at sniffing out which cuts would be “intolerable” and which would be merely inconvenient. Meanwhile, keeping on the popular Petraeus will help the President manage the difficult politics of drawdown in Iraq and Afghanistan. He’s a nonpartisan figure who is a master of the Congressional hearing and has a great deal of credibility with the national security establishment. His presence will make it easier for everyone from generals in the field to foreign policy experts to accept the idea that each step towards withdrawal represents movement towards overall victory.

As Kaplan says, this hardly guarantees that things will magically run smoothly; the challenges are going to be difficult. But it’s a good play.