I'm not going into an analysis of Donald Rumsfeld's mistakes as Defense Secretary, but I will bring up his penchant for strange jargon and odd sayings. For me, he will always be remembered for the weird words coming from him rather than being a good leader (which he wasn't). My all-time favorite was an enigmatic jet-lagged(?) piece of philosophy.
"Reports that say that something hasn't happened are always interesting to me, because as we know, there are known knowns; there are things we know we know. We also know there are known unknowns; that is to say we know there are some things we do not know. But there are also unknown unknowns -- the ones we don't know we don't know."
And here are a few more that will be more memorizable than the above quote.
"I believe what I said yesterday. I don't know what I said, but I know what I think, and, well, I assume it's what I said."
"I would not say that the future is necessarily less predictable than the past. I think the past was not predictable when it started."
There are many websites that have Rumsfeld quotes, here's one but Google for more.