Don't fence me in: Gates explains why the president might not want a Pentagon chief all cozy with the Secretary of State

From a recent talk
by former Defense Secretary Robert Gates. I wonder if you have to be an old
Sovietologist to think like this:

Now here's the other side of that coin. And it's something that folks don't often
think about. The truth of the matter is that if you're the president of the
United States, you may not want a secretary of State and a secretary of Defense
to get along famously, and who are on exactly the same page, because if you've
got Defense and State on different sides of an issue, then the president is in
the position of kind of the Chinese menu. He can take a little from column A
and a little from column B.

But if the two of them are on exactly the same page, it's
not a trivial matter for the president to ignore the recommendations of both
the secretary of State and the secretary of Defense. 

(HT to KP)