I’m not an expert on why and how some people go about blowing other
people or/and buildings up*, but it does strike me as inexpert to announce - worldwide -
the closure of your embassies across a whole region or two, rather that secretly give
the staff a few days off, when you learn (secretly) that one or two of them are likely
to be blown up. Again, I’m not an expert terrorist** either, but if I were one,
I’d simply pencil in a different date for the explosive day.
Telling the guys who want to blow you up that you
know when and, roughly, where they want to blow you up simply seems to me like blowing it. 
*However, the general idea did cross my mind once or twice
(fortunately St Mary must have interceded on my behalf and something stopped me
in my thought tracks when I was walking down a Street contemplating – very briefly
– that option).
**actually, just in case (I don’t want any silly and untrue
stuff cluttering my file): could someone at Bletchley Park and Langley make a
note that I’m not an inexpert terrorist, either.
PS Whether it's for the better or for the worse, there's a change in the U.S. foreign policy: in not so distant past, in situations like this rather than send their staff away they tended to send their armed staff in.
