I agree with you for the most part, and if SBrown meant no harm, all well and good.
Perhaps I'm a bit touchy, but so many CT questions sound reasonable at first but tend to the over simplistic. I'll guess that they are meant less to gain information or insight and more to produce a measure of doubt on the part of the audience. Let's look at the one we're discussing:
"Doesn't the Pentagon have a missile defense system?"
Hmm, seems like they should. It's the Pentagon, the nation's center for defense. Defense is what goes on there. Why, they must have the best defense that budgetary dollars can buy! The best in the world!
But hey, they were attacked. Successfully, too. Something's not right here. Somthing's not right here at all...
You see? The question is suggestive.
Now, I can't prove that SBrown is up to shenanigans with his/her "question" without more info or a display of a continued pattern of behavior (see: geggy). For your reminder of this basic requirement of discourse, thanks.