I believe we knew all along the weapons went to Syria but timing is everything because we announce we know where they went it's up to the US to take action. tick-tock
You make a good point. Also something to consider:
W has been taking so much heat on this MWD thing, that the next time we take action on it the proof will be 100% infallable.
He may be laying low until that 100% proof is known to all, but that is a hugely risky course of action. I would still be more comfortable if he came out and provided much more info to everyone on what we do know about the MWD's.
Of course, then the left will start whining about how he did not do enough about it.