For a very very complete run down of contradictions and demonstrable falsehoods in the assertions of the swift boat veterans for (against?) truth see this page. Michael Froomkin sent me there.

I'd like to two bits which appear but are not contrasted on the page

from factcheck.org
"Larry Thurlow, who says he commanded a third Swift Boat that day, says "Kerry fled while we stayed to fight," and returned only later "after no return fire occurred.""

from USA Today

"Even those soldiers who didn't like Kerry had respect for him:
[snip]
""He was extremely brave, and I wouldn't argue that point," Thurlow says.""

Well I guess after all, he would.

It is amazing that it is possible to demonstrate that people making claims about things which happened over 30 years ago in front of few witnesses are so clumsy that it is possible to prove that they are liars. The Swift Boat Veterans for "Truth" seem to have managed one of the most incompetent smears in the long and sad history of human nastiness and dishonesty.