This is what Rafe Colburn has to say about the Bush National Guard issue. As usual, I think it is plain-speaking truth:

I would add that the Democrats could make hay if they pointed out that Kerry was staying above the fray and refraining from mudslinging in the way Bush has been doing with the Swift Boat issue. There’s an old neurolinguistic programming strategem called ‘talking in quotes’, in which you can both get your criticism across and yet maintain plausible deniability. Kerry should be saying, “Notice I’m not saying ‘Bush shirked his military duty and they’re concealing and lying about it’ the way he is talking about my war record in Vietnam. My campaign is about the issues, his is about diversion from his record.” See how that works? The criticism is ‘in quotes’ but Kerry’s not saying it.

Besides, although it appears to be counterintuitive, Kerry would do better taking a page from Karl Rove’s play book by attacking Bush’s perceived strengths rather than his recognized weaknesses. It is a simple issue to grasp; if someone hasn’t already gotten, or doesn’t care, that Bush was a shirker during Vietnam, there’s little chance of changing their mind at this stage and, as Coburn points out, it matters little. But taking the country down the drain during the past three and a half years in office is a different matter.