WASHINGTON - Sen. John F. Kerry expounds on many issues in his presidential campaign, but he's completely silent on one topic: his membership in Skull and Bones, Yale's infamous secret society. ``John Kerry has absolutely nothing to say on that subject. Sorry,'' said Kerry spokeswoman Kelley Benander. Kerry is a respected senator and a decorated Vietnam War combat veteran, but 36 years after he was initiated into what has been called the ``ultimate old boy network,'' he's wary of breaking the ultra-exclusive club's strict secrecy code. There's also another high-profile member of the club: President Bush. Bonesmen already are buzzing...