The timing of the leak that Chuck Hagel will be SecDef was no accident---given it was followed within moments that Susan Rice was withdrawing herself from consideration for Secretary of State. It was, I suspect, a shot at John McCain ( and his compatriot Lindsey Graham) that they may have won a battle, but they have lost the war. Nobody can honestly believe that John McCain is happy about Chuck Hagel being Secretary of Defense.
Chuck Hagel rather famously took down McCain during the primaries in 2007, condemning him for his irrational talk about Iran. Hagel has also shown, on more than one occasion, that he found the warmongering of McCain/ Lieberman/Graham insane. McCain is renowned for holding a grudge. Hagel did not endorse him in 2008, and certainly never campaigned on his behalf. In fact, he made it plain he wouldn't have objected to running with Obama.
President Obama knew that McCain was spoiling for a fight. So he gave him one---one that McCain cannot win. How does he go against Hagel who is a Republican, more popular with the military than McCain, and a guy from the Infantry? Hagel is about diplomacy over war. That just makes McCain's head explode. It also renders him now completely powerless as he moves over to Foreign Relations and any influence with the SecDef history. Remember, the military is McCain's bailiwick. Obama just slammed the door on his access.
And let's not forget that McCain is now even more unpopular for being perceived as "bullying" a highly educated woman of color. That likely won't soon be forgotten.
I'd say what we just saw was Checkmate.