There are likely several different motives at work, mutually reinforcing each other and varying from one member of Kerry's boat crew to another. Here's another motive to add to the stew: the desire to have a mark of distinction through association with a public figure.
Who would pay much attention to any of Kerry's boat crew unless they told flattering "war stories" about him? He is famous and successful and they have hitched themselves to him, like little sucker fish.
As for the swift boat vets who are hostile to Kerry, I am inclined to believe them on appearances alone. In years of opposition research work, I have found to my surprise that allegations against a candidate from people who know him almost always have an element of truth, even if murky on the facts.
For real whoppers, look to the flattering claims and stories that a candidate tells about himself and their explanations about negative information. Unless the news media dislike a candidate, they rarely give close scrutiny to a candidate's biographical claims.
Oddly, for some candidates and public officials, there is a sense of thrill and a boost to the ego in being able to tell lies and embellishments in public and get away with it. In such cases, a political career is not just something that they do but is integral to their conception of who they are.
The worst liars as candidates tend to be those who from their youth desperately wanted to be in public office and whose campaign pitch has a large element of self-praise and does not put the primary focus on issues. In the worst cases, they seem to have what psychologists call borderline personality disorder and have a nasty underside to them.
Kerry, who is living out his youthful ambition to be president, fits the profile of the self-obsessed politician. In office, his lying, dishonesty, and viciousness toward opponents would be of Clintonian proportions and potentially deadly to the country.
So far, we have a dozen or so Kerry Swift Boat comrades who support him-- they were the ones used as props at the convention.
And we have 250 or so SBV's who challenge Kerry's version of his service time in Vietnam and his fitness to be Comm. in Chief.
This has yet to play out. If Kerry is INDEED telling the truth about his service, we should expect 100's of SBV's out there to surface--maybe not as an organized group--to validate Kerry's version.
If we don't get dozens more if not 100's more coming forth in defense of Kerry, the conclusion one might draw is that the vast majority of those who served with Kerry question Kerry's version of his service experience, i.e. Kerry has not been truthful.
Or we could also conclude that of all the people Kerry served with, only 13 or so are Democrats who would vote for him anyway and the rest are Republicans who wouldn't.
I'm waiting to hear how many men who served with Kerry and support him stick their necks out like the anti-kerry SBV's have done.