It doesn't MATTER whether we attack Kerry's lies about his military record or NOT. Kerry's team started with the attacks on Bush BEFORE anybody had said a word about his record. He will continue with those attacks no matter what.
When Republicans make nice-nice with the Democrats, it makes no difference - they will keep on comparing Bush's record with Kerry's and bad-mouthing Bush. If nobody criticizes the obvious lies and revisions in Kerry's record, then he will just keep on hitting Bush and nobody will challenge him.
You assume that the Dems have manners, morals, and a conscience. None of the above are true.