No...this it'd have to be an all-American city; one with which every Joe and Jane American can identify...not a communist holdout.
Besides, the bay area Leftists, like their French counterparts, would ultimately claim that they were attacked only because they didn't appease the terrorists enough.
Your points are well taken, but I will stick with San Francisco. Somehow, it just seems like the best fit--communist holdout and terrorist appeasers notwithstanding...